
TOTAL ECLIPSE OF THE SUN, 1860, FROM TARRAGONA. 



St.N, Moon and Stars. 



SUN, MOON, AND STARS. 



ASTRONOMY FOR BEGINNERS. 



AGNES GIBERNE, 

AUTHOR OF "THE WORLD'S FOUNDATIONS," "THE OCEAN OF AIR, 1 

ETC. 

WITH A PREFACE 

BY THE 

REV. C. PRITCHARD, M. A., F. R. S., 

SAVILIAN PROFESSOR OF ASTRONOMY IN THE UNIVERSITY OF OXFORD. 



"One glory of the sun, and another glory of the moon, and another glory 
of the stars ; for star differeth from star in glory." i Cor. 15:41. 

" Lo, these are parts of His ways: but how little a portion is heard of Him! 
but the thunder of His power who can understand?" Job 26:14. 



NEW AND REVISED EDITION. 

AMERICAN TRACT SOCIETY, 

150 NASSAU STREET, NEW YORK. 

\ 



COPYRIGHT, 1893, 
AMERICAN TRACT SOCIETY. 



PREFACE TO REVISED EDITION. 



In the course of even a few years changes 
of necessity take place in so progressive a science 
as Astronomy. Some new discoveries are made, 
some new ideas are started, some old beliefs 
have to be given up. When the twentieth thou- 
sand of the English edition of " Sun, Moon, and 
Stars" was called for, it seemed to me that the 
time had come for a thorough revision of the 
whole : for a bringing up of the information 
contained therein, as far as possible, up to date. 

In the carrying out of this aim no trouble has 
been spared, and able friends have generously 
given time to helping me. Many old passages 
have been omitted and many new ones inter- 
polated, large portions of chapters have been 
rewritten, and the two last chapters are almost 
fresh ones. My little book will, I hope, go forth 
replenished with new vigor for a new campaign. 

AGNES GIBERNE. 
Worton House, 

Eastbourne, December, 1892. 



PREFACE. 



The pages of this little book on a great sub- 
ject were submitted to my criticism while passing 
through the press, with a request from a friend 
that I would make any suggestions which might 
occur to me for its improvement. Naturally 
such a request was entertained in the first in- 
stance' with hesitation and misgiving. But after 
a rapid perusal of the first sheet I found my 
interest awakened and then gradually secured ; 
for the book seemed to me to possess certain 
features of no ordinary character, and, in my judg- 
ment, held out the promise of supplying an un- 
doubted want, thus enabling me to answer a 
question which I have been often asked, and 
which had as often puzzled me, to the effect, 
" Can you tell me of any little book on Astronomy 
suited to beginners V I think that just such a 



6 Preface. 

book is here presented to the reader. For the 
tale of the Stellar Universe is therein told with 
great simplicity and perhaps with sufficient com- 
pleteness, in an earnest and pleasant style, equal- 
ly free, I think, from any considerable inaccuracy 
or any unpardonable exaggeration. We have 
here the outlines of elementary astronomy, not 
merely detailed without mathematics, but to a 
very great extent expressed in untechnical lan- 
guage. Success in such an attempt I am inclined 
to regard as a considerable feat, and one of much 
practical utility. 

For the science of astronomy is essentially a 
science of great magnitude and great difficulty. 
From the time of Hipparchus, some century and 
a half before the Christian era, down to the pres- 
ent day, its cultivation has severely taxed the 
minds of a succession of men endowed with the 
rarest genius. The facts and the truths of the 
science thus secured have been of very slow 
accretion ; but like all other truths, when once se- 
cured and thoroughly understood, they are found 
to admit of very simple verbal expression, and to 



Preface. y 

lie well within the general comprehension, and 
perhaps I may safely add within the sympathies 
of all educated men and women. 

Thus the great astronomers, the original dis- 
coverers of the last twenty centuries, have la- 
bored each in his separate field of the vast uni- 
verse of nature, and other men, endowed with 
other gifts, have entered on their labors, and by 
systematizing, correlating, and simplifying the 
expression of their results, have brought the 
whole within the grasp of cultivated men en- 
gaged in other branches of the varied pursuits of 
our complicated life. It is in this sort of order 
that the amelioration and civilization of mankind 
have proceeded, and at the present moment are, 
I hope and believe, rapidly proceeding. 

It was, I suspect, under this point of view, 
though half unconsciously so, that my attention 
was arrested by the little book now presented to 
the reader. For we have here many of the chief 
results of the laborious researches of such men 
as Ptolemy, Kepler, Newton, Herschel, Fraunho- 
fer, Janssen, Lockyer, Schiaparelli, and others — 
no matter where accumulated or by whom re- 



8 Preface. 

corded — filtered through the mind of a thought- 
ful and cultured lady, and here presented to 
other minds in the very forms wherein they have 
been assimilated and pictured in her own. And 
the forms and pictures in the main are true. It 
is in this way that the intellectual " protoplasm " 
of the human mind is fostered and practically dis- 
seminated. 

And then there is still another point of view 
from which this general dissemination of great 
truths in a simple style assumes an aspect of 
practical importance. I allude to the influences 
of this process on the imaginative or poetic side 
of our complex nature, and in support of the 
remark I shall quote from the pages of a work 
recently published by the Professor of Poetry in 
the University of Oxford : " Every new province 
of knowledge which science conquers, poetry may 
in turn enter into and possess. But this can only 
be done gradually. Before imagination can take 
up and mould the results of science these must 
cease to be difficult, laborious, abstruse. The 
knowledge of them must have become to the 



Preface. 9 

poet himself, and in some measure to his audi- 
ence, familiar, habitual, spontaneous. And here 
we see how finely science and poetry may interact 
and minister to each other .... Some beginning 
of such a reconciling process we may see here 
and there in those poems of ' In Memoriam,' in 
which the Poet Laureate has finely inwrought 
new truths of science into the texture of yearning 
affection and spiritual meditation ...."* 

Wordsworth in one of his prefaces has stated 
so clearly the truth on this subject that I cannot 
do better than give his words. " If the time 
should ever come," he says, " when what is now 
science becomes familiarized to men, then the 
remotest discoveries of the chemist, the botanist, 
the mineralogist, will be as proper objects of the 
poet's art as any upon which it can be employed. 
He will be ready to follow the steps of the man 
of science, he will be at his side, carrying sensa- 
tion into the midst of the objects of science itself. 
The poet will lend his divine spirit to aid the 

* " On Poetic Interpretation of Nature," by J. C. Shairp, 
LL. D., Edinburgh. David Douglas, 1877. 



io Preface. 

transfiguration and will welcome the being thus 
produced as a dear and genuine inmate of the 
household of man." 

It is for reasons such as those above stated 
that I heartily commend this little book to the 
attention of those of my countrymen and country- 
women who take an interest in the advancement 
of the intellectual progress and culture of society. 
The story of the Kosmos is told by the authoress 
in her own language, after her own method, and 
with no guidance of mine : in the main, I believe, 
as I have said, the story is correct; but I must 
disavow the responsibility of every detail. 

C. PRITCHARD. 

Oxford, September 2, 1879. 



AUTHOR'S PREFACE. 



Little remains to me, as needing to be said 
about my little book, after the most kind words 
of Prof. Pritchard. 

For years past I have had it in my mind to 
endeavor to supply some day, so far as might be, 
that of which there appeared to be a serious 
want — a plain and easily-to-be-understood Intro- 
duction to Astronomy. My wish has been to 
make it, not merely a text-book for school use, 
though possibly it may serve for that also, but 
a volume of sufficient interest for general read- 
ing ; not merely a book adapted for intelligent 
boys and girls, though I hope it may be found 
serviceable for them also, but a volume fitted for 
" beginners " of all kinds, whether children, work- 
ing-men, or even grown people of the educated 
classes, who should have a desire to enter for the 
first time on the study of this fascinating science. 
The attempt, such as it is, has been at last accom- 
plished. 



12 Author s Preface. 

I trust that a second underlying object or 
thought may not be found to have been alto- 
gether fruitless. In the Book of Nature, side by 
side with the Book of Revelation, we may learn 
some things about our Father in heaven. It 
would be happiness to feel that I had helped any, 
however slightly, to look upward through nature 
unto nature's God. 

I have, lastly, to express my warm gratitude 
to Prof. Pritchard for the time and trouble he has 
so generously expended in looking through the 
proof-sheets of a work by one who, as a perfect 
stranger, had and could have no manner of claim 
upon him. A request made through a mutual 
friend, with doubt and uncertainty on my part, 
has met with a fulness of response and kindness 
utterly unexpected, and for which no words of 
thanks seem half sufficient. 

Eastbourne, September 5, 1879. 



CONTENTS 



PART I. 

I. THE EARTH ONE OF A FAMILY 17 

II. THE HEAD OF OUR FAMILY 28 

III. WHAT BINDS THE FAMILY TOGETHER? 41 

IV. THE LEADING MEMBERS OF OUR FAMILY. — FIRST GROUP-- 55 
V. THE LEADING MEMBERS OF OUR FAMILY.— SECOND GROUP 65 

VI. OUR PARTICULAR FRIEND AND ATTENDANT 76 

VII. VISITORS 88 

VIII. LITTLE SERVANTS 96 

IX. NEIGHBORING FAMILIES IO5 

X. OUR NEIGHBORS' MOVEMENTS Il8 

PART II. 

I. MORE ABOUT THE SOLAR SYSTEM I35 

II. MORE ABOUT THE SUN 149 

III. YET MORE ABOUT THE SUN 162 

IV. MORE ABOUT THE MOON 172 

V. YET MORE ABOUT THE MOON l82 

VI. MERCURY, VENUS, AND MARS I94 



1 4 Contents. 

VII. JUPITER 209 

VIII. SATURN 219 

IX. URANUS AND NEPTUNE 227 

X. COMETS AND METEORS 236 

XI. MORE ABOUT COMETS AND METEORS — 244 

PART III. 

I. MANY SUNS 257 

II. SOME PARTICULAR SUNS 266 

III. DIFFERENT KINDS OF SUNS 278 

IV. GROUPS AND CLUSTERS OF SUNS - 287 

V. THE MILKY WAY ___ 296 

VI. READING THE LIGHT 307 

VII. FURTHER THOUGHTS . 317 

TABLE OF SUBJECTS - 329 













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Sun, Moon, and Stars. 



CHAPTER I. 

THE EARTH ONE OF A FAMILY. 

" The heaven, even the heavens, are the Lord's : but the earth 
hath He given to the children of men." — Psa. 115 : 16. 

What is this world of ours ? 

Something very great — and yet something very 
little. Something very great compared with the 
things upon the earth ; something very little com- 
pared with the things outside the earth. 

And as our journey ings together are for a while 
to be away from earth, we shall find ourselves 
obliged to count her as something quite small in 
the great universe, where so many larger and 
mightier things are to be found — if indeed they 
are mightier. 

Not that we have to say good-by altogether to 
our old home. We must linger about her for a 

Sun, Moon, <?tc. 2 



1 8 Sun, Moon, and Stars, 

while before starting, and afterwards it will be often 
needful to come back, with speed swifter than the 
flight of light, that we may compare notes on the 
sizes and conditions of other places visited by us. 
But first of all : what is this earth of ours ? 

It was rather a pleasant notion which men held 
in olden days, that we — that great and important 
" We " which loves to perch itself upon a height — 
stood firm and fixed at the very centre of every- 
thing. 

The earth was supposed to be a vast flat plain, 
reaching nobody could tell how far. The sun rose 
and set for us alone ; and the thousands of stars 
twinkled in the sky at night for nobody's good ex- 
cept ours ; and the blue sky overhead was a crystal 
covering for the men of our earth, and nothing 
more. In fact, people seem to have counted them- 
selves not merely to have had a kind of kingship 
over the lower animals of our earth, but to have 
been kings over the whole universe. Sun, stars, 
and sky, as well as earth, were made for man, and 
for man only. 

This was the common belief, though even in 
those olden days there were some who knew better. 
But the world in general knows better now. 



The Earth one of a Family. 19 

Earth the centre of the universe ! Why, she 
is not that of even the particular family in the 
heavens to which she belongs. For we do not stand 
alone. The earth is one of a family of worlds, and 
that family is called The Solar System. And so 
far is our earth from being the head of the family 
that she is not even one of the more important 
members. She is merely one of the little sisters 
as it were. 

Men not only believed the earth, in past days, 
to be at the centre of the universe, but also they 
believed her to remain there without change. Sun, 
moon, stars, planets, sky, might move, but never 
the earth. The solid ground beneath their feet, 
that at least was firm. Every day the sun rose and 
set, and every night the stars in like manner rose 
and set. But this was easily explained. We on 
our great earth stood firm and still, while sun, 
moon, stars, went circling round us once in every 
twenty-four hours, just for our sole and particular 
convenience. What an important personage man 
must have felt himself then in the great Universe ! 

Once again, we know better now ! 

For it is the earth that moves, and not the sun ; 
it is the earth that moves, and not the stars. The 
daily movements of sun and stars, rising in the 



20 Sun, Moon, and Stars. 

east, travelling over the sky and setting in the 
west, are no more real movements on their part 
than, when we travel in a railway-train, the seem- 
ing rush of hedges, telegraph-posts, houses, and 
fields is real. They are fixed and we are moving, 
yet the movement appears to us to be not ours but 
theirs. 

Still more strongly would this appear to be the 
case if there were no noise, no shaking, no jarring 
and trembling, to make us feel that we are not at 
rest. Sometimes when a train begins to move gent- 
ly out of a station, from among other trains, it is 
at the first moment quite impossible to say whether 
the movement belongs to the train in which we 
are seated or to a neighboring train. And in the 
motions of our earth there is no noise, no shaking, 
no jarring — all are rapid, silent, and even. 

If you were rising through the air in a balloon, 
you would at first only know your own movement 
by seeing the earth seem to drop away from be- 
neath you. And just so we can only know the 
earth's movements by seeing how worlds around us 
seem to move in consequence. 

Speaking now of the Universe, I mean thereby 
the whole material creation as far as the stars 



The Earth one of a Family. 2 1 

reach. Sometimes the word is used in this sense, 
and sometimes it is used only for a particular part 
of creation nearer to us than other parts. At pres- 
ent, however, we will put aside all thought of the 
second narrower meaning. 

The wisest astronomer living cannot tell us how 
far the stars reach. We know now that there is no 
firm crystal covering over our heads, dotted with 
bright points here and there ; but only the wide 
open sky or heaven, containing millions of stars, 
some nearer, some farther, some bright enough to 
be seen by us all, some only visible through a tele- 
scope. 

People talk often of the stars being "set in 
space ;" and the meaning of "space" is simply 
"room." Where you are must be space, or you 
could not be there. But it is when we get away 
from earth, and travel in thought through the wide 
fields of space, amid innumerable stars, that we 
begin to feel how vast it is, and what specks we 
are ourselves — nay, what a speck our very earth is, 
in this great and boundless creation. 

For there is no getting to the borders of space. 
As one telescope after another is made, each one 
stronger in power and able to reach farther than 
the last, still more and more stars are seen, and yet 



22 Sun, Moon, and Stars. 

more and more behind and beyond, in countless 
millions. 

It is the same all round the earth. The old no- 
tion about our world being a flat plain has been 
long since given up. We know her now to be a 
round globe, not fixed, but floating like the stars in 
space. We find this wonderfully described in the 
Bible, long before men knew or could know what 

the words meant : " He stretcheth out the north 

* 
over the empty place, and hangeth the earth 

UPON NOTHING."* 

When you look up into the sky from England, 
you are looking exactly in the opposite direction 
from where you would be looking up if you were 
in Australia. For Australia's " up " is England's 
"down," and England's " down" is Australia's " up." 

Or, to put it more truly, " up " is always in the 
direction straight away from this earth, on what- 
ever part of it you may be standing ; and " down " 
is always towards the centre of the earth. 

All round the globe, in north, south, east, west, 
whether you are in Europe, Asia, Africa, or Amer- 
ica, though you will see different stars in certain 
different quarters of the earth, still overhead you 
will find shining countless points of light. 
*Job 26 : 7. 



The Earth one of a Family. 23 

And now, what are these stars ? 

This is a matter on which people are often con- 
fused, and on which it is well to be quite clear be- 
fore going one step farther. 

Some of the stars you have most likely often 
noticed. The seven chief stars of the Great Bear 
are known to a large number of people ; and there 
are few who have not admired the splendid constel- 
lation of Orion. Perhaps you also know the W- 
shape of Cassiopeia, and the brilliant shining of 
Sirius, and the soft glimmer of the Pleiades. 

The different constellations or groups of princi- 
pal stars have been watched by men for long ages 
past. They are called the fixed stars, for they do 
not change. How many thousands of years ago 
they were first arranged by men into these groups, 
and who first gave them their names, we cannot 
tell. 

True, night by night, through century after 
century, they rise, and cross the sky, and set. But 
those are only seeming movements. Precisely as 
the turning round of the earth upon her axis, once 
in every twenty-four hours, makes the sun appear 
to rise and cross the sky and set in the day-time, so 
also the same turning of the earth makes the stars 
appear to do the same in the night-time. 



24 Sun, Moon, and Stars. 

There is another seeming movement among 
the stars which is only in seeming. Some come 
into view in summer which cannot be seen in win- 
ter ; and some come into view in winter which 
cannot be seen in summer. For the sun, moving 
on his pathway through the sky, hides those stars 
which shine with him in the day-time. And as he 
passes from point to point of his pathway through 
the constellations, he conceals from us fresh groups 
of stars by day and allows fresh groups to appear 
by night. Speaking generally, however, the stars 
remain the same year after year, century after cen- 
tury. The groups may still be seen as of old, fixed 
and unchanging. 

What are these stars ? 

Stars and planets have been spoken about. 
There is a great difference between the two. 

Perhaps if you were asked whether the sun is 
most like to a star or a planet, you would be rather 
at a loss. And many who have admired the bril- 
liant evening star, Venus, often to be seen after 
sunset, would be surprised to learn that the even- 
ing star is in reality no star at all. 

A star is a sun. Our sun is nothing more nor 
less than a star. Each one of the so-called " fixed 



The Earth one of a Family. 25 

stars " that you see shining at night in the sky is a 
sun like our sun ; only some of the stars are larger 
suns and some are smaller suns than ours. 

The main reason why our sun looks so much 
larger and brighter than the stars is that he is so 
very much nearer to us. The stars are one and all 
at enormous distances from the earth. By-and-by 
we will go more closely into the matter of their 
distance compared with the distance of the sun. 

At present it is enough to say that if many of 
the stars were placed just as near to us as our sun 
is placed they would look just as large and bright, 
while there are some that would look a great deal 
larger and brighter. And if our sun were to travel 
away from us to the distance of the very nearest 
of the little twinkling stars, he would dwindle 
down and down in size and brilliancy, till at last 
we should not be able to tell him apart from the 
rest of the stars. 

I have told you that the stars are called 
" fixed " because they apparently do not change 
from age to age. Though the movement of the 
earth makes them seem all to sweep past every 
night in company, yet they do not travel in and 
out among one another, or backwards and for- 
wards, or from side to side. At all events, if there 



26 Sun y Moon, and Stars. 

be such changes, they are so slow and so small as 
to be exceedingly difficult to find out. Each 
group of stars keeps its own old shape, as for hun- 
dreds of years back. 

But among these fixed stars there are certain 
stars which do go to and fro and backwards and 
forwards. Now they are to be seen in the middle 
of one constellation and now in the middle of 
another. These restless stars were long a great 
perplexity. Men named them Planets or Wan- 
derers. 

We know now that the planets are in reality 
not stars at all : and also that they are not nearly 
so far away from us as the fixed stars. In fact, 
they are simply members of our own family, the 
Solar System. They are worlds, more or less like 
the world we live in ; and they travel round and 
round the sun as we do, each more or less near to 
him ; and they depend upon him for heat and 
light in more or less the same manner as our- 
selves. 

Therefore, just as our sun is a star, and stars 
are suns, so our earth or world is a planet, and 
planets are worlds. Earth is the name we give 
to that particular world or planet on which we 
live. 



The Earth one of a Family. 27 

Planets may generally be known from stars 
by the fact that they do not twinkle. 

But the great difference between the two lies 
in the fact that a star shines by his own radiant 
dazzling light; whereas a planet shines by light 
reflected or borrowed from the sun' 



28 Sun, Moo7t y and Stars. 



CHAPTER II. 

THE HEAD OF OUR FAMILY. 

" The sun, which . . . rejoiceth as a strong man to run a 
race." — PSA. 19:4, 5. 

People began, very early in the history of the 
world, to pay close attention to the sun. And no 
wonder. We owe so much to his heat and light 
that the marvel would be if men had not thought 
much about him. 

Was the sun really any larger than he looked, 
and if so, how much larger was he ? And what 
was his distance from the earth ? 

These were two of the questions which puzzled 
our ancestors the longest. If once they could 
have settled exactly how far off the sun really 
was, they could easily have calculated his exact 
size ; but this was just what they could not do. 

So one man supposed that the sun must be 
quite near, and very little larger than he looked. 
Another thought he might be seventy-five miles 
in diameter. A third ventured to believe that he 
was larger than the country of Greece. A fourth 



The Head of our Family. 29 

was so bold as to imagine that he might even out- 
weigh the earth herself ! 

After a while many attempts were made to 
measure the distance of the sun ; and a great 
many different answers to this difficult question 
were given by different men, most of them very 
wide of the mark. 

It is only of late years that the matter has 
been clearly settled. And indeed it was found 
quite lately that a mistake of no less than three 
millions of miles had been made, notwithstanding 
all the care and all the attention given. But 
though three millions of miles sounds a great deal, 
yet it is really very little — only a tiny portion of 
the whole. 

For the distance of the sun from the earth is 
no less than about ninety -two millions of 

MILES. 

Ninety-two millions of miles ! Can you picture 
that to yourself ? 

Try to think what is meant by a thousand 
miles. Our earth is eight thousand miles in di- 
ameter. In other words, if you were to thrust a 
gigantic knitting-needle through her body, from 
the North Pole to the South Pole, it would have 
to be about eight thousand miles long. 



30 Sun, Moon, and Stars. 

To reach the thought of one million, you must 
picture one thousand times one thousand. Our earth 
is about twenty-five thousand miles round. If you 
were to start from the mouth of the River Ama- 
zon in South America, and journey straight round 
the whole earth on the equator till you came back 
to the same point, you would have travelled about 
twenty-five thousand miles. 

But that would be a long way from a million 
miles. You would have gone only once round 
the earth. Now a rope one million miles in 
length could be wrapped, not once only, but forty 
times, round and round the earth. 

And when you have managed to reach up to 
the thought of one million miles, you have then 
to remember that the sun's distance is ninety-two 
times as much again. So, to picture clearly to 
ourselves the actual meaning of " ninety -two mil- 
lions of miles " is not easy. 

Suppose it were possible to lay a railroad from 
here to the sun. If you could journey thither in a 
perfectly straight line, at the rate of thirty miles 
an hour, never pausing for one single minute 
night or day, you would reach the sun in just 
about three hundred and fifty years. 

Thirty miles an hour is a slow train. Suppose 



The Head of our Family. 3 1 

we double the speed, and make it an express train, 
rushing along at the pace of sixty miles an hour. 
Then you might hope to reach the end of your 
journey in one hundred and seventy-five years. 
If you had quitted this earth early in the reign of 
King George I., never stopping on your way, you 
would be just now, in the year 1893, arriving at 
the sun. 

So much for the sun's distance from us. Now 
as to his size. 

I have alread)^ mentioned that our earth's di- 
ameter — that is, her through measure, as, for in- 
stance, the line drawn straight from England 
through her centre to New Zealand — is about 
eight thousand miles. 

This sounds a good deal. But what do you 
think of the diameter of the sun being no less 
than eight hundred and sixty - five thousand 
miles ? 

The one is eight thousand miles, the other is 
eight hundred thousand miles ! 

Suppose you had a long slender pole which 
would pass through the middle of the earth, one 
end just showing at the North Pole and the other 
at the South Pole. You would need more than a 



32 Sun, Moon, and Stars. 

hundred and eight of such poles, all joined to- 
gether, to show the diameter of the sun. 

The sun seems not to be made of nearly such 
heavy materials as the earth. He is what astron- 
omers call less " dense,'' less close and compact in 
his make, just as wood is less dense and heavy 
than iron. 

Still his size is so enormous that if you could 
have a pair of gigantic scales, and put the sun into 
one scale and the earth with every one of her 
brother and sister planets into the other, the sun's 
side would go down like lightning. He would be 
found to weigh seven hundred and fifty times as 
much as all the rest put together. 

It would take more than twelve hundred thou- 
sands of little earths like ours, rolled into one 
huge ball, to make a globe as large as the sun. 

Suppose our earth were to dwindle down and 
down, smaller and smaller, till she became a tiny 
globe only one inch in diameter. Imagine the 
sun at the same time dwindling down in the same 
manner, and keeping the same proportion as to 
size. " Keeping the same proportion " means that 
he would still be twelve hundred thousand times 
as large as the earth, that his axis, or the straight 
line through his centre from North Pole to South 



The Head of our Family. 33 

Pole, would still be one hundred and eight times 
as long as the earth's axis. 

Then, side by side with the minute ball, one 
inch in diameter, you would see a great globe 
nine feet in diameter — half as high again as a tall 
man. 

And if you wish to gain a fair notion, not only 
of the sun's size, but of his distance from us, set 
such a nine-feet globe in a field, and move slowly 
round it a one-inch ball at a distance of three hun- 
dred and twenty yards. This may help you to 
understand. 

In the beginning of the seventeenth century a 
man named Fabricius was startled by the sight of 
a certain black spot upon the face of the sun. 

He watched till too dazzled to look any longer, 
supposing it to be a small cloud, yet anxious to 
learn more. Next day the spot was there still, 
but it seemed to have moved on a little way. 
Morning after morning this movement was found 
to continue, and soon a second spot, and then a 
third spot, were observed creeping in like manner 
across the sun. After a while they vanished, one 
at a time, round his edge, as it were ; but after 
some days of patient waiting on the part of the 

Sun, Moon, etc. ^5 



34 Sun, Moon, and Stars. 

lookers-on, they appeared again at the opposite 
edge and once more began their journey across. 

Fabricius seems to have been the first, but he 
was not the last, to watch sun-spots. Many as- 
tronomers have given close attention to them. 
Modern telescopes, and the modern plan of look- 
ing at the sun through darkened glass, have made 
this possible in a way that was not possible two or 
three hundred years ago. 

The first important discovery made through the 
spots on the sun was that the sun turns round upon 
his axis just in the same manner that the earth 
turns round upon hers. Instead of doing so once in 
the course of each twenty-four hours, like the earth, 
he turns once in the course of about twenty-five 
days. 

It must not be supposed that the spots seen now 
upon the sun are the same spots that Fabricius saw 
in the reign of our James I. There is perpetual 
change going on — new spots forming, old spots 
vanishing, one spot breaking into two, two spots 
joining into one, and so on. Even in a single hour 
great alterations are sometimes seen to take place. 

Still many of the spots do remain long enough 
and keep their shapes closely enough to be watched 



The Head of our Family. 35 

from day to day, and to be known again as old 
friends when they reappear after being about 
twelve days hidden on the other side of the sun. 
So that the turning of the sun upon his axis has 
become, after long and careful examination, a cer- 
tain fact. 

For more than thirty years one astronomer 
kept close watch over the spots on every day that 
it was possible to see the sun. Much was learned 
from his perseverance, and far more has been 
learned since. 

Two or three months may be counted a fair 
medium length of time for a spot to endure, while 
one has been known to exist as long as eighteen 
months. This, however, was exceptional. 

It seems pretty sure that these spots are caused 
by some kind of cyclones, great in extent and vio- 
lence, on the surface of the sun. 

We do not yet know with absolute certainty 
whether the sun is through and through one vast 
mass of heated gases ; but this is the opinion now 
generally held ; and the older idea of a possibly 
solid and even cool interior is at present given up. 

The round, shining disc or flat surface seen by 
all of us is called the " photosphere " or " light- 
sphere/' It has a tolerably well-defined edge or 



36 Sun, Moon, and Stars. 

"limb," and dazzles the eyes with its intense radi- 
ance. 

Of the photosphere Prof. Young writes, "All 
that we can learn as to the temperature and consti- 
tution of the sun makes it hardly less than certain 
that the visible surface, which is called the photo- 
sphere, is just a sheet of self-luminous cloud, pre- 
cisely like the clouds of our own atmosphere, with 
the exception that the droplets of water, which 
constitute terrestrial clouds, are replaced in the 
sun by drops of molten metal and that the solar 
atmosphere in which they float is the flame of a 
burning, fiery furnace, raging with a fury and an 
intensity beyond all human conception." And 
again, "The photosphere is a shell of luminous 
clouds, formed by the cooling and condensation of 
the condensible vapors at the surface where ex- 
posed to the cold of outer space." Of course the 
words " cooling " and " cold " are comparative 
terms only, in reference to such a neighborhood. 

Outside the photosphere lies the chromosphere or 
chromatosphere or sierra. This, seen at the edge of 
the sun, against the sky, has been described as " a 
quivering fringe of fire ;" and since the sun turns 
incessantly upon his axis, presenting each hour 
fresh portions of his surface in that position, it 



The Head of our Family. 37 

follows that the whole surface of the sun is one 
restless, billowy ocean of fire. The waves of the 
sea on a stormy day, perceived in the far distance 
rising and breaking the horizon-line, may serve as 
a tiny illustration, only that in the sun the billows 
are of fire, not water. Think what their height 
must be that they should be thus visible — even 
through a telescope — at a distance of nearly nine- 
ty-three millions of miles ! 

It is believed that the chromosphere is formed 
of such gases — chiefly hydrogen — as refuse to be 
condensed into the molten clouds which form the 
photosphere. 

Sun, as well as earth, possesses an atmosphere, 
but it is an atmosphere very different in descrip- 
tion ; not fitted like ours to support life, not " shal- 
low and quiet," but " an envelope of matter, partly 
gaseous and partly perhaps pulverulent or smoke- 
like, many thousand miles in depth, and always 
most profoundly and violently agitated."* 

Outside the chromosphere are to be seen bright, 
rose-colored " prominences " — extraordinary protu- 
berant shapes of enormous size, though dwindled 
down to smallness by distance. During an eclipse, 
when the dark body of the moon glides between 
* Prof. Young. 



38 Sun, Moon, and Stars. 

the sun and us, exactly covering the photosphere 
and hiding its glare, these crimson jagged tips 
stand out distinctly beyond the edge of sun and 
moon. Once upon a time they could be seen only 
at such seasons, during the brief space of a total 
eclipse ; but the spectroscope now enables astrono- 
mers to see them in full daylight. Careful watch- 
ing for hours together has thus become possible, 
not to speak of photographing. 

They are found to be prolongations of the red 
chromosphere — that sea of glowing gas which 
bathes the whole body of the sun. They too con- 
sist of gas, mainly of hydrogen gas, rising like 
enormous mountain-billows out of that fiery ocean. 
" Flames " they are often called, though not con- 
suming flames, like those which burn away sub- 
stances in our earthly atmosphere, but rather 
continuously glowing masses of gas, luminous 
with vehement heat. 

The height of these prominences has been re- 
peatedly measured. Some are so lofty that ten 
little earths such as ours might be heaped up, one 
upon another, without reaching the top. One was 
seen to tower to the extent of 300,000 miles— an 
outrush of radiant gas from the sun almost incredi- 
ble ! 




Orbits of the Planets. 



The Head of gut Family. 39 

Outside the prominences lies the corona — a 
beautiful crown of soft light, plainly visible to the 
naked eye during an eclipse. Some of the stream- 
ers of this mysterious surrounding crown, or at- 
mosphere, reach to a distance of a million miles. 
Little is yet known as to its true nature and use. 

To return to the subject of sun-spots. 

Although we cannot yet speak positively as to 
the constitution of the sun, we can at least say that 
he is a vast centre of light and heat, and a scene of 
terrific storms, beyond anything ever seen on this 
quiet little earth of ours. Certainly no such thing 
as quietness may be found there ! The wildest 
and fiercest turmoil of fire and hurricane prevails 
unceasingly ; and when the blazing surface is torn 
open, darker though still fiery depths seem to be 
exposed, becoming apparent as " spots " to us in 
our distant world. Beside the dark spots there 
are also spots of dazzling brilliance, standing out 
upon even that radiant background. Such extra- 
bright spots, which come and go, and at times 
change their form with great rapidity, are named 
faculce — a Latin word meaning " torches." 

It sounds to us startling to read of jets of fire 
and smoke from Mt. Vesuvius ten thousand feet 
in height, or of a river of lava in Iceland pouring 



40 Sun, Moon, and Stars. 

in an unbroken stream for fifty miles. But what 
shall be thought of tongues of glowing hydrogen 
mounting to a height of one or two hundred thou- 
sand miles above the sun-surface ? What shall be 
thought of a solar plane long enough to be folded 
three or four times around our solid earth ? What 
shall be thought of the awful rush of incandescent 
gases, borne along at a rate of one or two or even 
three hundred miles in a second ? What shall be 
thought of the vast rents in this raging ocean, rents 
often from fifty to one hundred thousand miles 
across ? 

Fifty thousand miles ! A mere speck, seen 
from earth, scarcely visible without a telescope, yet 
large enough to contain seven worlds like ours 
flung in together. One of the bigger spots meas- 
ured was so enormous that eighteen earths might 
have been laid in a row across the breadth of it ; 
and to have filled up the entire hole about one 
hundred earths would have been necessary. 

Only in speaking of a " hole " we must not pic- 
ture a cavern, with solid walls and floor. If a sun- 
spot be a hollow at all, which is not certain, it is a 
hollow framed and walled by glowing gases, in a 
state of inconceivable turmoil, heat, and fury. 



What Binds the Family Together? 41 



CHAPTER III. 

WHAT BINDS THE FAMILY TOGETHER? 

" Dost thou know . . . the wondrous works of Him which is 
perfect in knowledge ?" Job 37 : 16. 

" The day is Thine, the night also is Thine ; Thou hast pre- 
pared the light and the sun. . . . Thou hast made summer and 
winter." — Psa. 74: 16, 17. 

What is it which binds together all the mem- 
bers of the Solar System ? 

Ah, what? Why should not the sun at any 
moment rush away in one direction, the earth in a 
second, the planets in half-a-dozen others ? What 
is there to hinder such a catastrophe ? 

Nothing — except that they are all held together 
by a certain close family tie ; or, more correctly, 
by the powerful influence of the head of the 
family. 

This mysterious power which the sun has, and 
which all the planets have also in their smaller 
degrees, is called Attraction. Sometimes it is 
named Gravitation or Gravity. 

When we speak, as we often do, of the law of 
attraction or gravitation, we mean simply this — 



42 Sun, Moon, and Stars. 

that throughout the universe, in things little and 
great, is found a certain wonderful something in 
constant action which we call a "law." What the 
"something" may be man cannot tell, for he 
knows it only by its effects. But these effects are 
seen everywhere, on all sides, in the earth and in 
the universe. It is well named in being called a 
" law," for we are compelled to obey it. None but 
the Divine Lawgiver who made this law could for 
a single moment interrupt its working. 

What causes an apple to fall to the ground 
when it drops from the branch ? Why should it 
not instead rise upwards ? Because, of course, it is 
heavy, or has weight. But what is weight ? 

Simply this: that the earth draws or drags 
everything downwards towards herself by the 
power of attraction. Every substance, great or 
small, light or heavy, is made up of tiny atoms. 
Each one of these atoms attracts or draws all the 
other atoms towards itself; and the closer they 
are together, the more strongly they pull one 
another. 

The atoms in a piece of iron are much closer 
than the atoms in a piece of wood ; therefore the 
iron is called the "more dense" of the two, and its 



What Binds the Family Together? 43 

weight or "mass" is greater. The more closely 
the atoms are pressed together, the greater the 
number of them in a small space and the more 
strong the drawing towards the earth, for the 
earth draws each one of these atoms equally. 
That is only another way of saying that a thing is 
"heavier." 

If you drop a stone from the top of a cliff will 
it rise upwards or float in the air ? No, indeed. 
The pull of the earth's attraction, dragging and 
still dragging downward, makes it rush through 
the air, with speed quickening each instant, till it 
strikes the ground. 

Every single atom in every single body pulls 
every other atom, whether far or near. The 
nearer it is, the stronger always the pulling. 

We do not always feel this, because the very 
much greater attraction of the earth hides, or 
smothers as we may say, the lesser attraction of 
each small thing for another. But though you 
and I might stand side by side upon earth and feel 
no mutual attraction, yet if we could mount up a 
few thousands of miles, far away from earth, and 
float in distant space, there we should find our- 
selves drawn together and unable to remain 
apart. 



44 Sun, Moon, and Stars. 

Now precisely as an apple falling from a tree 
and a stone dropping from a cliff are dragged 
downward to the earth, just so our earth and all 
the planets are dragged downward towards the 
sun and towards each other. The law of the 
earth's attraction of all objects on its surface to 
itself was indistinctly suspected a very long time 
ago ; but it was the great Newton who first discov- 
ered that this same law was to be found working 
among the members of the whole Solar System. 

The sun attracts the earth, and the earth at- 
tracts the sun. But the enormous size of the sun 
compared with our earth — like a great nine-feet 
globe beside a tiny one-inch ball — makes our 
power of attraction to be quite lost sight of in his, 
which is so much greater. 

We come now to another question. If the sun 
is pulling with such power at the earth and all her 
sister planets, why do they not fall down upon 
him ? What is to prevent their rolling some day 
into one of those deep rents in his fiery en- 
velope ? 

Did you ever tie a ball to a string and swing it 
rapidly round and round your head ? 

If you did, you must have noticed the steady 



What Binds the Family Together? 45 

outward pull of the ball. The heavier the ball 
and the more rapid its whirl, the stronger the pull 
will be. Let the string slip, and the rush of the 
ball through the air to the side of the room will 
make this yet more plain. 

Did you ever carry a glass of water quickly 
along, and then, on suddenly turning a corner, 
find that the water has not turned with you ? It 
has gone on in its former direction, leaving the 
glass and spilling itself on the floor. 

The cause in both cases is the same. Here is 
another "law of nature," so called. Though we 
can neither explain nor understand why and how 
it is so, we see it to be one of the fixed rules of 
nature, working everywhere alike throughout the 
whole universe. 

The law, as we see it, seems to be this : Every- 
thing which is at rest must remain at rest until 
set moving by some cause outside of or independ- 
ent of itself; and everything which is once set 
moving must continue moving in a straight line 
until checked. 

According to this, a cannon-ball lying on the 
ground ought to remain there until it is set in 
motion ; and, once set in motion by being fired 
from a cannon, it ought to go on for ever. 



46 Sun, Moon, and Stars. 

Exactly so — if nothing stops it. But the 
earth's attraction draws the cannon-ball down- 
ward, and every time it strikes the ground it is 
partly checked. Also each particle of air that 
touches it helps to bring it to rest. If there were 
no earth and no air in the question, the cannon- 
ball might rush on in space for thousands of 
years. 

Why did the water get spilled ? 

Because it necessarily continued moving in a 
straight line. Your sudden change of direction 
compelled the solid glass to make the same 
change, but the liquid water was free to go 
straight on in its former course, so it obeyed this 
law and did go on. 

Why did the ball pull hard at the string as you 
swung it round ? 

Because at each instant it was striving to obey 
this same law and to rush onward in a straight 
line. The pull of the string was every moment 
fighting against that inclination and forcing the 
ball to move in a circle. 

Just such is the earth's movement in her 
yearly journey around the sun. The string hold, 
ing in the ball pictures the sun's attraction hold- 
ing in the earth. The pulling of the ball outward 



What Binds the Family Together? 47 

in order to continue its course in a straight line 
pictures the pulling of our earth each moment to 
break loose from the sun's attraction and to flee 
away into distant space. 

For the earth is not at rest. Each tick of the 
clock she has sped onward over more than eigh- 
teen miles of her pathway through the sky. 
Every instant the sun is dragging, with all the 
great force of his attraction, to make her fall 
nearer to him. Every instant the earth is drag- 
ging, with all the great force of her rapid rush, to 
get away from him. These two pullings so far 
balance each other, or, more strictly, so far com- 
bine together, that between the two she journeys 
steadily round and round in her nearly circular 
orbit. 

If the sun pulled a little harder she would need 
to travel a little faster, or she would gradually go 
nearer to him. If the earth went faster, and the 
sun's attraction remained the same as it is now, 
she would gradually widen her distance. 

Indeed, it would only be needful for the earth 
to quicken her pace to about five-and-twenty miles 
a second, the sun's power to draw her being un- 
changed, and she would then wander away from 
him for ever. Day by day we on our earth should 



48 Sun, Moon, and Stars. 

travel farther and farther away, leaving behind us 
all light, all heat, all life, and finding ourselves 
slowly lost in darkness, cold, and death. 

For what should we do without the sun ? All 
our light, all our warmth, come from him. With- 
out the sun, life could not exist on the earth. 
Plants, herbage, trees would wither ; the waters of 
rivers, lakes, oceans would turn to masses of ice ; 
animals and men would die. Our earth would 
soon be one vast, cold, forsaken tomb of darkness 
and desolation. 

I have spoken before about the old-world 
notion that our earth was a fixed plane, with the 
sun circling round her. 

When the truth dawned slowly upon some 
great minds, anxious only to know what really 
was the truth, others made a hard struggle for the 
older and pleasanter mode of thinking. It went 
with many sorely against the grain to give up all 
idea of the earth being the chief place in the uni- 
verse. Also there was something bewildering 
and dizzying in the notion that our solid world is 
never for one moment still. 

But truth won the victory at last. Men con- 
sented slowly to give up the past dream and to 



What Binds the Family Together ? 49 

learn the new lesson put before them. We still 
talk of the sun rising and setting and of the stars 
doing the same. This is, however, merely a com- 
mon form of speech, which means just the op- 
posite. For instead of the sun and stars moving, 
it is the earth which moves. 

The earth has two distinct movements. In- 
deed, I ought to say that she has three, but we 
will leave all thought of the third for the present. 

First : She turns round upon her axis once in 
every twenty-four hours. 

Secondly : She travels round the sun once in 
about every three hundred and sixty -five days 
and a quarter. 

No wonder our ancestors were startled to learn 
that the world, which they had counted so im- 
movable, was perpetually spinning like a hum- 
ming-top and rushing through space like an 
arrow. 

You may gain some clear notions as to the 
daily rising and setting of our sun with the help 
of an orange. Pass a slender knitting-needle 
through the orange from end to end, and hold it 
about a yard distant from a single candle, in a 



Sun, Moon, etc. 



50 Sun, Moon, and Stars. 

room otherwise darkened. Let the needle or axis 
slant somewhat, and turn the orange slowly round 
and round upon it. 

The candle does not move ; but as the orange 
turns, the candle-light falls in succession upon 
each portion of the yellow rind. Half of the 
orange is always in shade and half is always in 
light ; while at either side, if a small fly were 
standing there, he would be passing out of shade 
into candle-light or out of candle-light into 
shade. 

Each spot on our earth moves round in turn 
into half-light, full-light, half-light, and darkness ; 
or, in other words, has morning dawn, midday 
light, evening twilight, and night. Each spot on 
our earth would undergo regularly these changes 
every twenty-four hours throughout the year, 
were it not for another arrangement which so far 
affects this that the North and South Poles are, by 
turns, cut off from the light during many months 
together. 

Thus the sun is in the centre of the Solar Sys- 
tem, turning slowly on his axis ; and the earth 
and the planets travel round him, each spinning 
like a teetotum, so as to make the most of his 
bright warm rays. But for this spinning move- 



What Binds the Family Together? 51 

ment of the earth, our day and night, instead of 
being each a few hours long, would each last six 
months. 

You may notice that, as you turn the orange 
steadily round, the outside surface of the skin has 
to move much more slowly in those parts close to 
the knitting-needle than in those parts which 
bulge out farthest from it. Near the North and 
South Poles the surface of our earth travels slowly 
round a very small circle in the course of twenty- 
four hours. But at the equator every piece of 
ground has to travel about twenty-five thousand 
miles in the same time ; so that it rushes along at 
the rate of more than one thousand miles an hour. 
A man standing on the earth, at the equator, is 
being carried along at this great speed, not through 
the air — for the whole atmosphere partakes of the 
same rapid motion — but with the air, round and 
round the earth's axis. 

Now about the movement of the earth — her 
yearly journey round the sun. 

While she moves, the sun, as seen from the 
earth, seems to change his place. First he is ob- 
served against a background of one group of stars, 
then against a second, then against a third. Not 
that the stars are visible in the day-time when the 



52 Sun, Moon, and Stars, 

sun is shining, but their places are well known in 
the heavens ; and also they can be noted very soon 
after he sets or before he rises, so that the constel- 
lations nearest to him may each day be easily 
found out. 

Of course in old times the sun was thought to 
be really taking this journey among the stars, and 
men talked of " the sun's path " in the heavens. 
This path was named " the Ecliptic," and we use 
the word still, though we know well that the 
movements are not really his, but ours. 

As the earth's daily movement causes day and 
night, so the earth's yearly movement causes 
spring, summer, autumn, and winter. 

A few pages back I mentioned in passing one 
slight yet important fact which lies at the root of 
this matter about the seasons. 

The earth, journeying round the sun, travels 
with her axis slanting. 

Put your candle in the middle of the table, and 
stand at one end, holding your orange. Now let 
the knitting-needle, with the orange upon it, so 
slant that one end shall point straight over the 
candle, towards the upper part of the wall at the 
farther end of the room. Call the upper end, so 
pointing, the North Pole of your orange. 



What Binds the Family Together ? 53 

You will see that the candle-light falls chiefly 
upon the upper half of the orange ; and as you turn 
it slowly, to picture day and night, you will find 
that the North Pole has no night and the South 
Pole has no day. That is summer in the northern 
hemisphere and winter in the southern. 

Walk round next to one side of the table, 
towards the right hand, taking care to let the 
knitting-needle point steadily still in exactly the 
same direction, not towards the same spot, for that 
would alter its direction as you move, but towards 
the same wall. Stop, and you will find the candle 
lighting up one half of your orange, from the 
North to the South Poles. Turn it round slowly, 
never altering the slope of the axis, and you will 
see that every part of the orange comes by turns 
under the light. This is the Autumnal Equinox, 
when days and nights all over the world are equal 
in length. 

Walk on to the other end of the table, still let- 
ting the needle slope and point steadily as before. 
Now the candle-light will shine upon the lower or 
South Pole, and the North Pole will be entirely in 
the shade. This is summer in the southern hem- 
isphere and winter in the northern. 

Pass on to the fourth side of the table, and 



54 Sun, Moon, and Stars. 

once more you will find it as at the second side — 
equal light from North Pole to South Pole. This 
will be the Spring Equinox. 

It is an illustration that may be easily prac- 
tised; but everything depends upon keeping the 
slant of the needle or axis unchanged throughout. 
If it be allowed to point first to right and then to 
left, first towards the ceiling and then towards the 
wall, the attempt will prove a failure. 



■■■' 



The Leading Members of our Family. 55 



CHAPTER IV. 

THE LEADING MEMBERS OF OUR FAMILY. — FIRST 
GROUP. 

" The heavens declare the glory of God, and the firmament 
showeth His handywork." — Psa. 19: 1. 

The chief distinction between stars and planets 
is, as before said, that the stars shine entirely by 
their own light, while the planets shine chiefly, if 
not entirely, by reflected light. 

The stars are suns, great globes of heat and 
light. The planets simply receive the light of the 
sun, and shine with a brightness not their own. 

A lamp shines by its own light ; but a looking- 
glass, set in the sun's rays and flashing beams in 
all directions, shines by reflected light. In a dark 
room it would be dark. If there were no sun to 
shine upon Mars or Venus, we should see no 
brightness in them. The moon is like the planets 
in this. She has only borrowed light to give, and 
none of her own. 

Any one of the planets, removed to the distance 
of the nearest fixed star, would be invisible to us. 
Reflected light will not shine nearly so far as the 



56 Sun, Moon, and Stars. 

direct light of a burning body. There may be 
thousands or millions of planets circling round the 
stars — those great and distant suns — just as our 
brother-planets circle round our sun, but it is im- 
possible for us to see them. The planets which 
we can see are close neighbors compared with the 
stars. I do not mean that they are near in the 
sense in which we speak of nearness upon earth. 
They are only near in comparison with what is so 
very much farther away. 

For a while we must now leave alone all 
thought of the distant stars, and try to gain a 
clear idea of the chief members of our own family 
circle — that family circle of which the sun is the 
head, the centre, the source of life and warmth 
and light. 

There are two ways in which astronomers group 
the planets of the Solar System. 

One way is to divide them into the Inferior 
Planets and the Superior Planets. 

As the earth travels in her pathway round the 
sun, two planets travel on their pathways round 
the sun nearer to him than ourselves. If the 
pathway or orbit of our earth were pictured by a 
hoop laid upon the table, with a ball in the centre 




Figs, i, 2, and 4, Saturn. In Fig. i the ring is represented as seen edgeways. 
Fig. 3> Jupiter. The dark spot represents a satellite passing acioss the disc of 
the planet. 

Figs. 5 and 6, Mars ; two views of nearly opposite hemispheres. The darker 
markings are believed to be water, and the lighter portion land. The white patch 
at the pole is probably ice or snow. 



Sun, Moon and Staks* 



p. 50. 



The Leading Members of our Family. 57 

for the sun, then those two planets would have 
two smaller hoops of different sizes within ours, 
and the rest would have larger hoops of different 
sizes outside ours. The two within are called infe- 
rior planets, and the rest outside are called supe- 
rior planets. 

A round hoop would not make a good picture 
of an orbit. For the yearly pathway of our earth 
is not in shape perfectly round, but slightly oval ; 
and the sun is not exactly in the centre, but a lit- 
tle to one side of the centre. This is more or less 
the case with the orbits of all the planets. 

But the laying of the hoops upon the table 
would give no bad idea of the way in which the 
orbits really lie in the heavens. The orbits of all 
the chief planets do not slope and slant round the 
sun in all manner of directions. They are placed 
almost in the same plane, as it is called — or, as we 
might say, in the same flat. In these orbits the 
planets all travel round in the same direction. 
One may overtake a second on a neighboring 
orbit, and get ahead of him, but one planet never 
goes back to meet another. 

In speaking of the. orbits, I do not mean that 
the planets have visible marked pathways through 
the heavens, any more than a swallow has a vis- 



58 Sun, Moon, and Stars. 

ible pathway through the sky, or a ship a marked 
pathway through the sea. Yet each planet has his 
own orbit, and each planet so distinctly keeps to 
his own that astronomers can tell us precisely 
whereabouts in the heavens any particular planet 
will be, at any particular time, long years before- 
hand. 

There is also another mode of grouping the 
planets besides dividing them into superior and 
inferior planets. 

By this other mode we find two principal groups 

or quartettes of planets, separated by a zone or 

belt of a great many very small planets. 

r Mercury. 
Venus. 
Earth. 



First Group .... 



L Mars. 
The Asteroids or Planetoids. 
Jupiter. 
Saturn. 



Second Group . 



Uranus. 
ta Neptune. 



The first four are small compared with the last 
four, though much larger than any in the belt of 
tiny Asteroids. 

It was believed at one time that a planet had 



The Leading Members of our Family, 59 

been discovered nearer to the sun than Mercury, 
and the name Vulcan was given to it. But no 
more has been seen of Vulcan, and his existence 
is so doubtful that we must not count him as a 
member of the family without further informa- 
tion. 

Mercury is very much smaller than our earth. 

The diameter of the earth is eight thousand 
miles, but the diameter of Mercury is less than 
three thousand miles — not even half that of the 
earth. 

Being so much nearer to the sun than our- 
selves, the pulling of his attraction is much 
greater, and this has to be balanced by greater 
speed, or Mercury would soon fall down upon the 
sun. Our distance from the sun is ninety-two 
millions of miles. Mercury's distance is only 
about one-third of ours ; and instead of travelling, 
like the earth, at the rate of eighteen miles each 
second, Mercury, when nearest to the sun, goes at 
the mad pace of thirty-five miles each second. It 
is a good thing the earth does not follow his exam- 
ple, or she would soon break loose from the sun's 
control altogether. 

The earth takes more than three hundred and 



6o Sun, Moon, and Stars. 

sixty-five days, or twelve months, to journey round 
tlie sun in her orbit. That is what we call " the 
length of our year." But Mercury 's year is hardly 
eighty-eight days, or not quite three of our months. 
No wonder ! — when his pathway is so much shorter 
and his speed so much greater than ours. So 
Mercury has four years to one year on earth ; and 
a person who had lived on Mercury as long as five 
earthly years would then be twenty years old. 
The increased number of birthdays would scarcely 
be welcome in large families, supposing we could 
pay a long visit there. 

The sun, as seen from Mercury, looks about 
four and a half times as large as from here, the 
heat and glare being increased in proportion. No 
moon has ever been found belonging to Mercury. 

Venus, the second inferior planet, is nearly the 
same size as our earth. Seen from the earth, she 
is one of the most brilliant and beautiful of all the 
planets. Her speed is four miles a second faster 
than ours, and her distance from the sun is about 
two-thirds that of our own ; so that the orbit of 
Venus lies half-way between the orbit of Mercury 
and the orbit of the earth. Her year is nearly 
two hundred and twenty-five days, or seven and a 



The Leading Members of our Family. 61 

half of our months. Some astronomers at one 
time thought that they caught glimpses of a 
moon near Venus : but this is still quite doubt- 
ful ; and indeed it is believed to have been a 
mistake, since for a long while it has not been 
seen again. 

Venus and Mercury are only visible as morn- 
ing and evening planets. Venus, being farther 
from the sun, does not go before and follow after 
him quite so closely as Mercury, and she is there- 
fore the longer within sight. 

When Venus, travelling on her orbit, comes 
just between the sun and us, her dark side is 
turned towards the earth, and we can catch no 
glimpse of her. When she reaches that part of 
her orbit which is farthest from us, quite on the 
other side of the sun, her great distance from us 
makes her light seem less. But about half-way 
round on either side she shows exceeding bril- 
liancy ; and that is the best view we can get of 
her. 

Seen through a telescope, Venus undergoes 
what we call " phases," like the moon. That is to 
say, we really have " new Venus/' " quarter Ve- 
nus/' " half Venus," "full Venus," and so on. 
Mercury passes through the same phases, but his 



62 Sun, Moon, and Stars. 

smallness and distance make them more difficult 
to see. 



Next to the orbit of Venus comes the orbit 
of our own Earth, the third planet of the first 
group. 

Mars, the fourth of the inner quartette, but 
the first of the superior planets, is a good deal 
smaller than Venus or the earth. The name 
Mars, from the heathen god of war, was given on 
account of his fiery reddish color. Mars is better 
placed than Venus for being observed from earth. 
When he is at the nearest point of his orbit to us 
we see him full in the blaze of sunlight ; whereas 
Venus, at her nearest point, turns her bright face 
away. 

The length of the day of Mars, or in other 
words the time he takes to turn upon his axis, 
is only forty minutes longer than that of the 
earth. 

Mars* journey round the sun is completed in 
the course of six hundred and eighty -seven days, 
not much less than two of our years. His dis- 
tance from the sun is about one hundred and 



The Leading Members of our Family. 63 

forty millions of miles, and his speed is fourteen 
miles a second. We shall find, with the increas- 
ing distance of each planet, that the slower pace 
balances the lessened amount of the sun's attrac- 
tion. 



Passing on from Mars, the last of the first 
group of planets, we reach the belt of Asteroids, 
sometimes called Planetoids, Minor Planets, or 
Telescopic Planets. They are so tiny that Mer- 
cury is a giant compared with the largest among 
them. 

The zone of space containing all these little 
planets is more than a hundred millions of miles 
broad. Their orbits do not lie flat in almost the 
same plane, but slant about variously in a very 
entanged fashion. If a neat model were made of 
this zone, with a slender piece of wire to repre- 
sent each orbit, it would be found impossible to 
lift up one wire without pulling up all the rest 
with it. Those asteroids lying nearest to the sun 
take about three of our years to travel round him, 
and those lying farthest take about six of our 
years. 

New members of the group are very often 



64 Sun, Moon, and Stars. 

found. The number of asteroids now known 
• amounts to nearly three hundred and fifty. 

Pallas, the largest, is about six hundred miles 
in diameter. Vesta, the brightest, is about three 
hundred miles. Nearly eighteen thousand Vestas 
would be needed to make one globe equal to our 
earth in size. 



The Leading Members of our Family. 65 



CHAPTER V. 

THE LEADING MEMBERS OF OUR FAMILY.— 
SECOND GROUP. 

" O Lord* how manifold are Thy works ! in wisdom hast 
Thou made them all." Psa. 104 : 24. 

Leaving behind us the busy zone of Plane- 
toids hurrying round and round the sun in com- 
pany, we cross a wide gap and come upon a very 
different sight. 

The distance from the sun which we have 
now reached is more than four hundred and 
eighty millions of miles, or over five times as 
much as the earth's distance ; and the sun in the 
heavens shows a diameter not one-fifth of that 
which we are accustomed to see. Slowly — yet 
not slowly — floating onwards through space in his 
far-off orbit, we find the magnificent planet Jupi- 
ter. 

Is eight miles each second slow progress? 
Compared with the wild whirl of little Mercury, 
or even compared with the rate of our own earth's 
advance, we may count it so ; but certainly not 
compared with our notions of speed upon earth. 

Sun, Moon, etc. C 



66 Suit, Moon, and Stars. 

Eight miles each second is five hundred times as 
fast as the swiftest express train ever made by 
man. No mean pace that for so enormous a 
body ! 

For Jupiter is the very largest of all the mem- 
bers of the Solar System except the sun him- 
self — quite the eldest brother of the family. His 
longest diameter is nearly eighty-eight thousand 
miles, or about eleven times as long as that of 
earth. Though, in proportion to his great bulk, 
not nearly so heavy as our earth, yet his bulk is 
so vast that more than twelve hundred earths 
would be needed to make one Jupiter. 

It must not, however, be forgotten that there 
is a certain amount of uncertainty about these 
measurements of Jupiter. He seems to be so 
covered with a dense atmosphere and heavy 
clouds that it is quite impossible for us to learn 
the exact size of the solid body within — if, indeed, 
any part of him is solid. 

Jupiter does not travel alone. Borne onwards 
with him and circling round him are four or five 
moons ; one about the same size as our own moon, 
and of the others three are larger. The nearest 
of the four, which till lately were counted to be 
the full number, speeds round him in less than 



The Leading Members of our Family. 67 

two of our days. The most distant, though over 
a million miles away, takes scarcely seventeen 
days to accomplish its long journey. A fifth 
moon is now believed to exist. 

Jupiter and his moons make quite a little sys- 
tem by themselves — a family circle within a fam- 
ily circle. 

Like the smaller planets, Jupiter spins upon 
his axis ; and he does this so rapidly that, not- 
withstanding his great size, his day lasts only ten- 
hours instead of twenty-four hours like ours. 

But if Jupiter's day is short, his year is not. 
Nearly twelve of our years pass by before Jupiter 
has travelled once completely round the sun. So 
a native of earth who had just reached his thirty- 
seventh year would, on Jupiter, be only three 
years old. 

Passing onward from Jupiter, ever farther and 
farther from the sun, we leave behind us another 
vast and empty space — empty as we count empti- 
ness, though it may be that there is in reality no 
such thing as emptiness throughout the length 
and breadth of the universe. 

The width of the gap which divides the path- 
way of Jupiter from the pathway of his giant 



68 Sun, Moon, and Stars. 

brother-planet Saturn is nearly five times as much 
as the width of the gap separating the earth from 
the sun. The distance of Saturn from the sun 
is not much less than double the distance of Ju- 
piter. 

With this great space in our rear we come 
upon another large and radiant planet, the centre, 
like Jupiter, of another little system, though it 
can only be called " little " in comparison with 
the much greater Solar System of which it forms 
a part. 

Saturn's diameter is less than that of Jupiter, 
but the two come near enough to be naturally 
ranked together. Nearly seven hundred earths 
would be needed to make one globe as large as 
Saturn. But here again the dense and cloudy 
envelope makes us very uncertain about the 
planet's actual size. Saturn is like Jupiter in 
being made of lighter materials than our earth ; 
and also in his rapid whirl upon his axis, the 
length of his "day" being a little over ten of 
our hours. 

From Jupiter's speed of eight miles each sec- 
ond we come down in the case of Saturn to about 
five miles each second. And Jupiter's long annual 
journey looks almost short seen beside Saturn's 



The Leading Members of our Family. 69 

longer journey of almost thirty years. A man 
aged sixty, according to otir fashion of reckoning 
time, would on Saturn have just kept his second 
birthday. 

The system or family of Saturn is yet more 
wonderful than that of Jupiter. Not five only, 
but eight, moons travel ceaselessly around Saturn, 
each in its own orbit ; and in addition to the 
eight moons he has revolving round him three 
magnificent rings. These rings, as well as the 
moons, shine, not by their own brilliancy, for they 
have none, but by borrowed sunlight. 

The farthest of the moons wanders in his lonely 
pathway about two millions of miles away from 
Saturn. The largest of them is believed to be 
about the same size as the planet Mars. 

Of the three rings circling round Saturn, al- 
most exactly over his equator, the inside one is 
dusky, purplish, and transparent ; the one outside 
or over that is very brilliant ; and the third, out- 
side the second, is rather grayish in hue. 

Another vast gap — more enormous than the 
last. It is a wearisome journey. From the orbit 
of Jupiter to the orbit of Saturn at their nearest 
points was five times as much as from the sun to 



jo Sun, Moon, and Stars. 

the earth. But from the orbit of Saturn to the 
orbit of Uranus, the next member of the sun's 
family, we have double even that great space to 
cross. 

Still, obedient to the pulling of the sun's 
attractive power, Uranus wanders onward in his 
wide pathway round the sun at the rate of four 
miles per second. Eighty-four of our years make 
one year of Uranus. He is attended by four 
moons, and thus forms a third smaller system 
within the Solar System ; but he may have other 
satellites also, as yet undiscovered. In size he is 
sixty-four times as large as our earth. 

One more mighty chasm of nine hundred mil- 
lions of miles, for the same distance which sepa- 
rates the pathway of Saturn from the pathway of 
Uranus separates also the pathway of Uranus from 
the pathway of Neptune. Cold and dark and 
dreary indeed seems to us the orbit on which this 
banished member of our family circle creeps 
round the sun, in the course of one hundred and 
sixty-five years, at the sluggish rate of three miles 
per second. 

On the planet Saturn the quantity of light and 
heat received from the sun is not much more than 



The Leading Members of Our Family. 7 1 

a hundredth part of that which we are accustomed 
to receive on earth. But by the time we reach 
Neptune the great sun has faded and shrunk in 
the distance until to our eyes he looks only like 
an exceedingly brilliant and dazzling star. 

We know little of this far-off brother, Neptune, 
except that he is rather larger than Uranus, being 
nearly thirty -five thousand miles in diameter; 
that he has at least one moon ; and also that, like 
Uranus, he is made of materials lighter than those 
of earth, but heavier than those of Jupiter or 
Saturn. 

After all, it is no easy matter to gain clear 
ideas as to sizes and distances from mere state- 
ments of " so many miles in diameter " and " so 
many millions of miles away." A " million miles " 
carries to the mind a very dim notion of the actual 
reality. 

Now if we can in imagination bring down all 
the members of the Solar System to a small size, 
keeping always the same proportions, we may 
find it a help. 

" Keeping the same proportions " means that 
all must be lessened alike, all must be altered in 
the same degree. Whatever the supposed size of 



72 Sun, Moon, and Stars. 

the earth may be, Venus must be still about the 
same size as the earth, Saturn seven hundred 
times as large, and so on. Also, whatever the dis- 
tance of the earth from the sun, in miles or yards 
or inches, Mercury must still be one-third as far, Ju- 
piter still five times as far, and thus with the rest. 

First as to size alone. Suppose the earth is 
brought down to a small globe exactly three 
inches in diameter. It will be a very smooth 
globe. Not only men and houses, but mountains, 
valleys, seas, will all have shrunk to so minute a 
size as to be quite invisible to the naked eye. 

Fairly to picture the other members of the 
Solar System in due proportion, you will have 
them as follows : * 

Mercury and Mars will be balls smaller than 
the earth, and Venus nearly the same size as 
the earth. Uranus and Neptune will be each 
somewhere about a foot in diameter. Saturn will 
be twenty-eight inches, and Jupiter thirty-two 
inches, in diameter. The sun will be a huge daz- 
zling globe twenty-six feet in diameter. No won- 
der he weighs seven hundred and fifty times as 
much as all his planets put together ! 

* " Other Worlds," by R. A. Proctor. 



The Leading Members of Ottr Family, 73 

Next let us picture the system more exactly on 
another and smaller scale. 

First think of the sun as a brilliant globe two 
feet in diameter, floating in space far from this 
earth of ours. 

At a distance of about eighty-two feet travels a 
tiny ball, no bigger than a grain of mustard-seed, 
passing slowly round the sun — slowly, because, 
as size and distance are lessened, speed must in 
due proportion be lessened also. This is Mer- 
cury. 

At a distance of about one hundred and 
forty - two feet from the central sun travels 
another tiny ball, the size of a pea. This is 
Venus. 

At a distance of two hundred and fifteen feet 
from the sun travels a third tiny ball, again the 
size of a pea. This is the Earth ; and her accom- 
panying Moon is no larger than a very small pin's 
head. 

At a distance of three hundred and twenty- 
seven feet from the sun travels a fourth tiny ball, 
the size of a rather large pin's head. This is 
Mars. 

Then comes a wide blank space, followed by a 
large number of minute grains of sand floating 



74 Sun, Moon, and Stars. 

round the sun in company, at distances varying 
from five hundred to six hundred feet. These are 
the Asteroids. Another wide blank space suc- 
ceeds the outermost of them. 

Nearly a quarter of a mile distant from the sun 
journeys a globe very different from those last 
described, being as large as a moderate-sized 
orange. Round him and with him, as he rolls 
slowly onward, travel five smaller balls, the 
biggest of them not much over a mustard- 
seed in size. These are Jupiter and his 
moons. 

Somewhat less than half a mile distant from 
the sun journeys another globe, about the 
size of a small orange. Eight tiny balls and 
three delicate rings circle slowly round him as 
he moves. These are Saturn and his belong- 
ings. 

More than three-quarters of a mile distant 
from the sun journeys another globe, about 
the size of a small plum, accompanied by 
four minute balls. These are Uranus and his 
moons. 

Lastly, at a distance of about a mile and 
a quarter from the sun, journeys one more 
globe, as large as a good -sized plum, with 



The Leading Members of Our Family. 75 

one tiny companion, pursuing his far-off jour- 
ney. 

These proportions as to size and distance,* if 
carefully studied, will serve to give a clearer idea 
of the Solar System as a whole than learning a 
long list of numbers would do. 

* From " Outlines of Astronomy," by Sir J. Herschel. 



j6 Sun, Moon, and Stars. 



CHAPTER VI. 

OUR PARTICULAR FRIEND AND ATTENDANT. 

" The moon walking in brightness." — Job 31 : 26. 

Come and let us pay a visit to the moon. 

We seem to feel a personal interest in her just 
because she is in so peculiar a sense our own 
friend and close attendant. The sun shines for 
us, but then he shines for all the members of the 
Solar System. And the stars — so many as we can 
see of them — shine for us too, but no doubt they 
shine far more brilliantly for other and nearer 
worlds. The moon alone seems to belong espe- 
cially to ourselves. 

Indeed we are quite in the habit of speaking 
about her as "our moon," Rather a cold and 
calm friend some may think her, sailing always 
serenely past, whatever may be going on beneath 
her beams ; yet she has certainly proved herself 
constant and faithful in her attachment. 

We have not very far to travel before reaching 
her — merely about two hundred and forty thou- 
sand miles. That is nothing compared with the 



Our Particular Friend and Attendant. 77 

weary millions of miles which we have had to 
cross to visit some members of our family. A 
rope two hundred and forty thousand miles long 
would fold neatly ten times round the earth at the 
equator. You know the earth's diameter — about 
eight thousand miles. If you had thirty poles, 
each eight thousand miles long, and could fasten 
them all together, end to end, one beyond another, 
you would have a rod long enough to reach from 
the earth to the moon. 

Let us take a good look at her before 
starting. 

She is very beautiful. That soft silvery light, 
so unlike sunlight or gaslight or any other kind of 
light, even electric light, has made her the darling 
of poets and the delight of all who love nature. 
Little children like to watch her curious markings, 
and to make out the old man with his bundle of 
sticks, or the eyes, nose, and mouth of the moon — 
not dreaming what those markings really are. 
And in moods of sadness how the pure calm 
moonlight seems to soothe the feelings ! Who 
would suppose that the moon's beauty is the 
beauty rather of death than of life ? 

The stars have not much chance of shining 



78 Sun, Moon, and Stars, 

through her bright rays. It is well for astrono- 
mers that she is not always at the full. 

But when she is how large she looks — quite as 
large as the sun, though in reality her size, com- 
pared with his, is only as a very small pin's head 
compared with a school globe two feet in diam- 
eter. Her diameter is little more than two thou- 
sand miles, or one-quarter that of our earth ; and 
her whole surface, spread out flat, would scarcely 
equal North and South America without any of 
the surrounding islands. 

The reason she looks the same size as the sun 
is that she is so very much nearer. The sun's dis- 
tance from us is more than one-third as many 
millions of miles as the moon's distance is thou- 
sands of miles. This makes an enormous difference. 

We call our friend a " moon," and say that she 
journeys round the earth, while the earth jour- 
neys round the sun. This is true, but it is only 
part of the truth. Just as certainly as the earth 
travels round the sun, so the moon also travels 
round the sun. And just as surely as the earth is 
a planet, so the moon also is a planet. It is a 
common mode of expression to talk about "the 
earth and her satellite." A no less correct, if not 
more correct, way would be to talk of ourselves as 



Our Particular Friend and Attendant. 79 

" a pair of planets/' journeying round the same 
sun, each pulled strongly towards him, and each 
pulling the other with a greater or less attraction, 
according to her size and weight. 

For the sun actually does draw the moon with 
more force than that with which the earth draws 
her. Only as he draws the earth with the same 
sort of force, and nearly in the same degree, he 
does not pull them apart. 

The moon, like the other planets, turns upon 
her axis. She does this very slowly, however ; and 
rather singularly she takes exactly the same time 
to turn once upon her axis that she does to travel 
once round the earth. 

The result of this is that we only see one face 
of the moon. If she turned upon her axis and 
journeyed round the earth in two different lengths 
of time, or if she journeyed round us and did not 
turn upon her axis at all, we should have views 
of her on all sides, as of other planets. But as 
her two movements so curiously agree, it happens 
that we always have one side of the moon towards 
us, and never catch a glimpse of the other side. 

And now we are ready to start on our journey 
of two hundred and forty thousand miles. 



8o Smi, Moon, and Stars. 

An express train, moving ceaselessly onward 
night and day at the rate of sixty miles an hour, 
would take us there in about five months and a 
half. But no line of rails has ever yet been laid 
from the earth to the moon, and no " lightning ex- 
press " has ever yet plied its way to and fro on 
that path through the heavens. Not on the wings 
of steam, but on the wings of imagination, we must 
rise aloft. Come — it will not take us long. We 
shall pass no planets or stars on the road, for the 
moon lies nearer to us than any other of the larger 
heavenly bodies. 

Far, far behind us lies the earth, and beneath 
our feet as we descend stretch the broad tracks of 
moonland. For " down ward' ' now means towards 
the moon and away from the distant earth. 

What a strange place w T e have reached ! The 
weird ghastly stillness of all around, and the awful 
dazzling cloudless glare, strike us first and most 
forcibly. Nothing quite like this have we ever felt 
on the earth. The close of the moon's long day — 
on this side of its globe — is approaching, and 
during a whole fortnight past the sun's fierce rays 
have been beating down on these shelterless 
plains ; yet, from lack of an atmosphere to retain 



Our Particular Friend and Attendant. 81 

sun-heat, the ground is cold — actually below zero — 
while the rays strike us with scorching power. It 
is much as on some lofty mountain-top, where icy 
cold and burning glare are combined ; only here 
all is immoderately intensified. 

Not a cloud to be seen overhead ; only a sky of 
inky blackness, with a blazing sun and thousands 
of brilliant stars and the dark body of our own 
earth, large and motionless and rimmed with light. 
Seen from earth, sun and moon look much the 
same size ; but seen from the moon the earth looks 
thirteen times as large as our full moon. 

Not even a little mistiness in the air to soften 
this fearful glare ! Air ! why, there is no air ; at 
least, not enough for any human being to breathe 
or feel. If there were air the sky would be blue, 
not black, and the stars would be invisible in the 
day-time. It looks strange to see them now shi- 
ning beside the sun. 

And then this deadly stillness ! Not a sound, 
not a voice, not a murmur of breeze or water. 
How could there be? Sound cannot be carried 
without air, and of air there is none. As for 
breeze — wind is moving air, and where we have 
no air we can have no wind. As for water — if 
there ever was any water on the moon it has en- 

Sun, Moon, etc . (5 



82 Sun, Moon, and Stars. 

tirely disappeared. We shall walk to and fro 
vainly in search of it now. No rivers, no rills, 
no torrents in those stern mountain - ramparts 
rising on every side. All is craggy, motionless, 
desolate. 

How very, very slowly the sun creeps over the 
black sky ; and no marvel, since a fortnight of 
earth-time is here but one day, answering to twelve 
hours upon earth. Cannot we find shelter some- 
where from this blaze of heat ? Yonder tall rock 
will do, casting a sharp shadow of intense black- 
ness. We never saw such shadows upon earth. 
There the atmosphere so breaks and bends and 
scatters about the light that outlines of shadows 
are soft and hazy, even the clearest and darkest of 
them, compared with this. 

How soon will the sun go down? One could 
wish for lessened glare, though by no means for 
greater cold. Meanwhile he is well worth study- 
ing — through this piece of neutral-tinted glass, 
without which no human eyes could face his splen- 
dor. For here no atmosphere lies between to act 
as a sheltering veil. What a magnificent object 
he is, with his radiant photosphere and crimson 
border, out of which spring sharp-toothed promi- 
nences, visible without the help of a telescope. 



Our Particular Friend and Attendant. 83 



No air between to hide them now, therefore no need 
of an eclipse to render them visible. See too the 
exquisite corona, a crown of pearly light, stretch- 
ing far on all sides in delicate lines and streams 
which die out slowly against the jet background. 
The black spots on the face of the sun are very 
distinct, and so also are the brilliant faculse. 

We must take a look around us now at moon- 
land, and not only sit gazing at the sun, though 
such a sky may well enchain attention. 

How unlike our earthly landscapes ! No sea, no 
rivers, no lakes, no streams, no brooks, no trees, 
bushes, plants, grass, or flowers, no wind or breeze ; 
no cloud or mist or thought of possible rain ; no 
sound of bird or insect, of rustling leaves or trick- 
ling water. Nothing but a changeless glare con- 
trasting with inky shadows — sun and earth and 
stars in a black heaven above, silent desolate 
mountains and plains below. 

For though we stand here upon a rough plain, 
this moon is a mountainous world. Ranges of 
rugged hills stretch away in the distance, with val- 
leys lying between — not soft green sloping earthly 
valleys, but steep gorges and precipitous hollows, 
all white dazzle and deep shade. 

But the mountains do not commonly lie in long 



84 Sun, Moon, and Stars. 

ranges as on earth. The surface of the moon 
seems to be dented with strange round pits, or 
craters, of every imaginable size. We had a bird's- 
eye view of them as we descended at the end of 
our long journey moonward. In many parts the 
ground appears to be quite honeycombed with 
them. Here are small ones near at haud and 
larger ones in the distance. The smaller craters 
are surrounded by steep ramparts of rock, the lar- 
ger ones by circular mountain-ranges. We have 
nothing quite like them on earth. 

Are they volcanoes? So it would seem, only 
no life, no fire, no action, remain now. All is dead, 
motionless, still. Is this verily a blasted world? 
Has it fallen under the breath of divine wrath, 
coming out scorched and seared ? Or is it rather 
passing through an aged and used-up phase of ex- 
istence, through which other planets also pass, or 
will pass, at some stage of their career ? The latter 
seems probable. 

We will move onward, and look more closely at 
that towering mass of rugged rocks beyond which 
the sun will by-and-by go down. Long jetty 
shadows lie from them in this direction. No 
wonder astronomers on earth can through their 



Our Particular Friend and Attendant. 85 

telescopes plainly see these black shadows contrast- 
ing with the glaring brightness on the other side. 

A "mass of rocks," I have said ; but as with 
our powers of rapid movement we draw near, we 
find a range of craggy mountains sweeping round 
in a vast circle. Such a height in Switzerland 
would demand many hours of hard climbing. But 
on this small globe attraction is a very different 
matter from what it is on earth. Our weight is so 
lessened that we can leap the height of a tall house 
without the smallest difficulty. No chamois ever 
sprang from peak to peak in his native Switzer- 
land with such amazing lightness as that with 
which we now ascend these mighty rocks. 

Ha ! what a depth on the other side ! We 
stand looking down into one of the monster cra- 
ters of the moon. A sheer descent of about six- 
teen thousand feet would land us at the bottom. 
Why, Mont Blanc itself is only some fifteen thou- 
sand feet in height. And what a crater ! Sixty- 
five miles across in a straight line from here to 
the other side, with these lofty rugged battlements 
circling round, while from the centre of the rough 
plain below a sharp cone-shaped mountain rises to 
about a quarter of the height of the surrounding 
range. 



86 Sun, Moon, and Stars. 

It is a grand sight ; peak piled upon peak, crag 
upon crag, sharp rifts or valleys breaking here 
and there the line of the narrow uplifted ledge, all 
wrapped in silent and desolate calm. There are 
many such craters as this on the moon, and some 
much larger. 

The sun slowly nears his setting and sinks be- 
hind the opposite range. How we shiver ! The 
last ray of sunlight has gone, and the ground, 
already below zero, is fast growing colder, pouring 
out into space all its little remnant of warmth. 
The change takes place with marvellous quickness. 
A deadly chill creeps over all around. A whole 
fortnight of earth-time must pass before the sun's 
rays will again touch this spot. Verily the con- 
trasts of climate in the moon, during the twelve 
long days and nights which make up her year, are, 
to say the least, unpleasant ! 

But though the sun is gone we are not in dark- 
ness. The stars shine with dazzling brightness, 
and the huge body of the earth, always seeming 
to hang motionless at one fixed point in the sky, 
gives brilliant light, though at present only half 
her face is lit up and half is in shadow. Still her 
shape is plainly to be seen, for she has ever round 
her a ring of light caused by the gathered shining 



Our Particular Friend and Attendant. 87 

of stars as they pass behind her thick atmosphere. 
She covers a space on the sky more than a dozen 
times as large as that covered by the full moon in 
our sky. 

It would be worth while to stay here and watch 
the half-earth grow into magnificent full-earth. 
But the cold is becoming fearful — too intense for 
even the imagination to endure longer. What 
must be the state of things on the other side of the 
moon, where there is no bright earth-light to take 
the place of the sun's shining, during the long 
two- weeks' night of awful chill and darkness ? 

Time for us to wend our way homeward from 
this desolate hundredfold-arctic scene. We have 
more to learn by-and-by about our friend and com- 
panion. For the present — enough. 



Sun, Moon, and Stars. 



CHAPTER VII. 



VISITORS. 



"Thou knowest not the works of God who maketh all." 
Eccles. 11:5. 

We come next to the very largest members of 
our Solar System. 

From time to time in past days— and days not 
very long past either — people were startled by the 
sight of a long-tailed star moving quickly across 
the sky, called a comet. We see such long-tailed 
stars still, now and then, but their appearance no 
longer startles us. 

It is hardly surprising, however, that fears 
were once felt. The great size and brilliancy of 
some of these comets naturally caused large ideas 
to be held as to their weight ; and the general un- 
certainty about their movements naturally added 
to the mysterious notions afloat with respect to 
their power of doing harm. 

A collision between the earth and a comet 
seemed no unlikely event ; and if it happened — 
what then ? Why, then of course the earth would 
be overpowered, crushed, burned up, destroyed. 



Visitors. 89 

So convinced were many on this point that the 
sight of a comet and the dread of the coming 
" end of the world " were fast bound together in 
their minds. 

Even when astronomers began to understand 
the paths of some of the comets, and to foretell 
their return at certain dates, the old fear was not 
quickly laid to rest. So late as the beginning of 
the present century, astronomers having told of 
an approaching comet, other people added the 
tidings of an approaching collision. " If a colli- 
sion, then the end of the world," was the cry ; and 
one worthy family, living and keeping a shop in a 
well-known town on the south coast of England, 
packed up and fled to America — doubtless under 
full belief that the destruction of the Old World 
would not include the destruction of the New. 

The nature of these singular bodies is some- 
what better known in the present day ; yet even 
now among all the members of the Solar System 
they are perhaps the ones about which we have 
most to learn. 

The nucleus or bright and star-like spot which, 
with the surrounding coma or "hair," we some- 
times call the " head " of the comet, is the densest 
and heaviest part of the whole. Comets may be 



90 Sun, Moon, and Stars. 

of enormous size, sometimes actually filling more 
space than the sun himself ; and their tails stream 
often for millions of miles behind or before them ; 
nevertheless they are among the lightest of the 
members of the Solar System. 

This excessive lightness greatly lessens the 
comet's power of harm-doing. In the rebound 
from all the old exaggerated fears men laughed at 
the notion of so light and delicate a substance 
working any injury whatever, and even declared 
that a collision might take place without people 
on earth being aware of the fact. It is now felt 
that we really know too little about the nature of 
the said substance to be able to say what might or 
might not be the result of a collision. A slight 
amount of injury to the surface of the earth might 
possibly take place. But of the " end of the world " 
as likely to be brought about by any comet in 
existence we may safely banish all idea. 

The word " comet " means " a hairy body," the 
name having been given from the hairy appear- 
ance of the light around the nucleus. 

A great many hundreds of different comets 
have been seen at different times by men — some 
large, some small, some visible to the naked eye, 
but most of them only visible through telescopes. 



Visitors. 9 1 

These hundreds are, there is no doubt, but a 
very small number out of the myriads ranging 
through the heavens. 

If you were seated in a little boat in mid-ocean, 
counting the number of fishes which in one hour 
passed near enough in the clear water for your 
sight to reach them, you might fairly conclude, 
even if you did not know the fact, that for every 
single fish which you could see there were tens of 
thousands which you could not see. 

Reasoning thus about the comets, as we watch 
them from our earth-boat in the ocean of space, we 
feel little doubt that for each one which we can 
see millions pass to and fro beyond reach of our 
vision. Indeed, so long ago as the days of Kepler 
that great astronomer gave it as his belief that the 
comets in the Solar System, large and small, were 
as plentiful as the fishes in the sea. And all that 
modern astronomers can discover only tends to 
strengthen this view. 

Why should the comets be called " visitors "? 

I call them so simply because many of them are 
visitors. Some, it is true, belong to the Solar Sys- 
tem. But even in their case strong doubts are felt 
whether they were not once visitors from a dis- 



92 Sun, Moon, and Stars. 

tance, caught in the first instance by the attraction 
of one of the larger planets and retained thencefor- 
ward, for a time at least, by the strong attraction 
of the sun. 

Every comet, like every planet, has his own 
orbit or pathway in the heavens, though the kind 
of orbit varies with different comets. 

There are, first, those comets which travel 
round and round the sun in " closed orbits " — that 
is, in a ring with joined ends— only the ring is 
always oval, not round. 

There are, secondly, those which travel in an 
orbit which may be closed ; but if so, the oval is so 
long and narrow, and the farther closed end is at 
so great a distance, that we cannot speak certainly. 

There are, thirdly, those which are decidedly 
mere visitors. They come from the far-off star- 
depths, flash once through our busy Solar System, 
forming radiant trains of light as they draw nearer 
to the sun ; and then they pass away in another 
direction, never to return. 

Only a small part of the orbits of these com- 
ets can be seen from earth ; but by careful 
attention astronomers learn something of the 
shape of the curve in which they travel. It is in 
that way possible to calculate, sometimes certainly 



Visitors. 93 

and sometimes uncertainly, whether a comet may 
be expected to return, or whether we have seen 
him for the first and the last time. By looking at 
part of a curve, the rest of which is hidden from us, 
we are able to judge whether that part belongs to 
a circle or an oval, or whether the two ends pass 
away in different directions and do not join. 

The comets, whether members of our family 
circle or visitors from a distance, are altogether 
very perplexing. They are often extremely large, 
yet they are always extremely light. They reflect 
the sun's brightness like a planet, yet in some 
measure they seem to shine by their own light, 
like a star. They obey the attraction of the sun, 
yet he appears to have a singular power of driving 
the comets' tails away from himself. 

For, however rapidly the comet may be rushing 
round the sun, and however long the tail may be, 
it is almost always found to stream in an opposite 
direction from the sun. An exception to this rule 
was seen in the case of a certain comet with two 
tails, one of which did actually point towards the 
sun ; but the inner tail may have been only a " jet " 
of unusual length, like in kind to the smaller jets 
often thus poured out from the nucleus. 



94 Sun, Moon, and Stars. 

Very curious changes take place in comets as 
they journey, especially as they come near the sun. 
One was seen in the course of a few days to lose 
both coma and tail, but as a general rule the tails 
increase with proximity to the sun, and lessen or 
vanish with distance. Travelling, as the comets 
do, from intense cold into burning heat, they are 
very much affected by the violent change of cli- 
mate. 

For the paths of the comets are such long ovals 
or ellipses that, while they approach the^sun very 
closely in one part of their " year," they journey to 
enormous distances in the other part. 

" Halley's Comet," which takes seventy-six of 
our years to travel round the sun, comes nearer to 
him than Venus and goes farther away from him 
than Neptune. 

As this comet draws gradually closer he has to 
make up for the added pull of the sun's increasing 
attraction by rushing onward with greater and 
greater rapidity, till he whirls madly past the sun, 
and then, with slowly slackening speed, journeys 
farther and farther away, creeps at length lazily 
round the farther end of his orbit in the chill dark 
neighborhood of Neptune, and once more travels 
towards the sun with growing haste. 



Visitors. 95 

" Encke's Comet " has a year of only three and 
a half of our years, so he may be said to live quite 
in our midst. But many comets go very much 
farther away than the one named after Halley. It 
is calculated of some that, if they ever return at all, 
it cannot be for many hundreds of years. 

" Newton's Comet," seen about two centuries 
ago, has a journey to perform of such length that 
he is not expected again to appear for several thou- 
sands of years. Yet at the nearest point in his 
orbit he approached the sun so closely that the 
heat which he endured was about two thousand 
times that of red-hot iron. Changes were seen to 
be taking place in his shape as he drew near to the 
sun and disappeared. Four days he was hidden 
in the sun's rays. He vanished with a tail stream- 
ing millions of miles behind him. He made his 
appearance again with a tail streaming millions of 
miles in front of him. But the precise nature of 
this wonderful phenomenon is at present beyond 
man's power to explain. 

So much for the largest members of our circle — 
largest though lightest — members some, visitors 
others. Now we turn to the smallest. 



96 Sun, Moon, and Stars. 



CHAPTER VIII. 

LITTLE SERVANTS. 
" All are Thy servants." — Psa. 119 191. 

If you walk out any night after dark, and watch 
the bright stars shining in a clear sky — shining as 
they have done for ages past — you will probably 
see now and then a bright point of light suddenly 
appear, dart along a little distance, and as sud- 
denly vanish. 

That which you have seen was not the begin- 
ning of a story, but in ninety-nine cases out of 
a hundred it was the end of a story. The little 
shooting-star was in existence long before you saw 
him, whirling through space with millions of little 
companions. But he has left them all and dropped 
to earth. He is a shooting-star no longer. 

If such a journey to the moon as the one de- 
scribed two chapters back were indeed possible, 
the voyage aloft would hardly be so easily and 
safely performed as is there taken for granted. 

Putting aside the thought of other difficulties, 



Little Servants* 97 

such as lack of conveyance and lack of air, there 
would be the danger of passing through a very- 
considerable storm of missiles — a kind of " celestial 
cannonade "— which, to say the least, would prove 
very far from agreeable. 

It will scarcely be believed what numbers of 
these shooting-stars or meteors — for they are not 
really stars at all — constantly fall to the earth. As 
she travels on her orbit, hurrying along at the rate 
of nineteen miles each second, she meets them by 
tens of thousands. They too, like the earth, are 
journeying round the great centre of our family. 
But they are so tiny, and the earth by comparison 
is so immense, that her strong attraction over- 
powers one after another, drags it from its path- 
way, and draws it to herself. 

And then it falls, flashing like a bright star 
across the sky, and the little meteor has come to 
his end. His myriads of companions, hastening 
still along their heavenly track— for the meteors 
seem to travel commonly in vast flocks or com- 
panies — might, had they sense, mourn in vain for 
the lost members of their family. 

Any one taking the trouble to watch carefully 
some portion of the sky after dark may expect to 
see each hour about four to eight of these shoot- 

Sun, Mocn, etc. H 



98 Sun, Moon, and Stars. 

ing-stars, except in the months of August and No- 
vember, when the number is much larger. About 
six in an hour does not sound a great deal. But 
that merely means that there have been six in one 
direction and near enough for you to see. Some- 
body else watching may have seen six in another 
direction, and somebody else a few miles away 
may have seen six more. It is calculated that in 
the course of every twenty-four hours over twenty 
millions of meteors fall to earth large enough to 
be visible as shooting-stars. # 

This is rather startling. What if you or I 
should some day be struck by one or other of these 
little bodies, darting as they do towards earth with 
speed swifter than that of a cannon-ball? True, 
they are not really stars, neither are they really 
planets. But they must be at least often much 
larger than a cannon-ball ; and a cannon-ball can 
destroy life. 

Over twenty millions every twenty -four, hours ! 
Does it not seem singular that we do not see them 
constantly dropping to the ground ? 

Doubtless we should see them, and feel them 
too, and dire would be the danger to human life, 
but for a certain protecting something folded 
round this earth of ours, to ward off the peril. 



Little Servants. 99 



That " something" is the earth's atmosphere. 
But for the thick soft air through which they 
have to pass, they would fall with violence, and 
perhaps would do much damage. 

As it is we are guarded. The " shooting-star," 
caught by earth's attraction, drops into her atmo- 
sphere, darting with extreme speed. The resist, 
ance of the air causes it to become intensely 
heated, till, with a flash of light, it vanishes into 
vapor. Meteors are believed to appear at a height 
of somewhere about seventy miles, and to disap- 
pear at a height of about fifty miles. So that in 
one instant's flash the shooting-star has travelled 
some twenty miles towards us. Then the light 
goes out. The little meteor is done for. It falls 
to earth still, but only as fine dust, sinking harm- 
lessly downward. 

Such small celestial bodies, thus travelling, do 
not always vanish so quickly. Now and again one 
actually reaches the ground ; and if a man were 
struck by such a stone he would undoubtedly be 
killed. A mason in France once had a narrow 
escape from such an accident. 

Bodies thus falling are called meteorites or aero- 
lites. Some are found no bigger than a man's fist, 
while others much exceed this size. There is 



ioo Sun, Moon, and Stars. 

one, kept carefully in the British Museum, which 
weighs three tons and a half; and we hear of 
another, lying in South America, between seven 
and eight feet in length. 

Such a sky-visitant would be very unwelcome 
in an English or American town. 

We must remember that, whatever size an 
aerolite may be when it reaches the earth, it must 
have been far bigger when journeying round the 
sun, since part of it has been vaporized during its 
rush through earth's atmosphere. 

Occasionally meteors are seen of a much larger 
type, slower in movement and longer visible. 
These sometimes burst with a loud explosion. 
They are then often called bolides or fire-balls. 

Early in the present century a meteor visited 
Normandy. It exploded with a noise like the roll 
of musketry, scattering thousands of hot stones 
over a distance of several miles. Happily no one 
seems to have been injured. Other such falls 
have taken place from time to time. 

Sometimes bright slowly-moving meteors have 
been seen looking as large as the moon. 

If we may liken comets to the fishes of the Solar 



Little Servants. 101 

System — and in their number, their speed, their 
varying sizes, their diverse motions, they may be 
fairly so likened — we may perhaps speak of mete- 
ors as the animalcule? of the Solar System. 

For in comparison with the planets they are, in 
the matter of size, as the animalculae of our ponds 
in comparison with human beings. In point of 
numbers they are countless. 

Take a single drop of water from some long- 
stagnant pond and place it under a powerful 
microscope. You will find it to be full of life, 
teeming with tiny animals darting briskly to and 
fro. The drop of water is in itself a world of 
living creatures, though the naked eye of man 
could never discover their existence. 

So too with the meteors. There is good reason 
to believe that the Solar System fairly teems with 
them. We talk of " wide gaps of empty space " 
between the planets ; but how do we know that 
there is any such thing as empty space to be found 
throughout all the sun's domain ? 

Not only are the meteors themselves countless, 
a matter easily realized, but the families or sys- 
tems of meteors appear to be countless also. They, 
like the systems of Jupiter and Saturn, are each a 
family within a family — a part of the Solar Sys- 



ID2 Sun, Moon, and Stars. 

tern | and yet a complete system by themselves. 
Each circles around the sun, and each consists of 
millions of these tiny bodies. When I say " tiny " 
I mean it of course only by comparison with 
other heavenly bodies. Many among them may 
possibly be hundreds of feet and even more in 
diameter, but the greater proportion appear to be 
much smaller. It is not impossible that multi- 
tudes beyond imagination exist so small in size 
that it is impossible we should ever see them, 
since their dying flash in the upper regions of our 
atmosphere would be too faint to reach our sight. 

The earth, travelling on her narrow orbit 
round the sun, crosses the track of about one 
hundred of these systems or rings. Sometimes 
she merely touches the edge of a ring, and some- 
times she goes into the very thick of a dense 
shower. 

Twice every year, for instance, on the 10th of 
August and the i ith of November, the earth passes 
through such a ring, and very many falling stars 
may be seen on those nights. Numbers of little 
meteors, dragged from their orbits and entangled 
in the earth's atmosphere, like a fly caught in a 
spider's web, give their dying flash and vanish. 



Little Servants. 103 

It used to be supposed that the August and 
November meteors belonged to one single system ; 
but now they are believed to be two entirely dis- 
tinct systems. 

Once in every thirty-three years we have a 
grand display of meteors in November, tens of 
thousands being visible in one single night. The 
meteors in that ring have their " year" of thirty- 
three earthly years, and once in the course of that 
long year our earth's orbit carries her deep into 
their midst. In this single November ring there 
are myriads upon myriads of meteors spreading 
through millions of miles of space. 

Yet this system is but one among many. 
There is no reason whatever to suppose that the 
streams of meteors cluster more thickly about the 
orbit of the earth than in other parts of the Solar 
System. No doubt the rest of the planets come 
across quite as many. 

Indeed the wonderful rings of Saturn are prob- 
ably formed entirely of meteors — millions upon 
millions of them whirling round the planet in a 
regular orbit-belt, lit up by the rays of the sun. 

Also it is believed that the meteor families 
cluster more and more closely in the near neigh- 
borhood of the sun, rushing wildly round him and 



I04 Sun, Moon, and Stars. 

falling by millions into the ocean of fire upon his 
surface. It has even been guessed that they may 
serve in part as fuel to keep up his intense heat. 

This we do not know with any certainty. But 
I have called these little bodies "servants/' for 
though we cannot yet say fully what is their precise 
use and purpose, we know that a use and pur- 
pose they must have. " All are God's servants," 
whether great or little. 

There is a curious cone-shaped light seen some- 
times in the west after sunset. It is called the 
" Zodiacal Light," and men have often been much 
puzzled to account for it. The shining is soft and 
dim, only to be seen when the sky is clear and 
only to be seen in the neighborhood of the sun. 
This too may be caused by reflected light from 
countless myriads of meteors gathering thickly 
round the sun. 



Neighboring Families. 105 



CHAPTER IX. 

NEIGHBORING FAMILIES. 

" Lift up your eyes on high, and behold who hath created 
these things, that bringeth out their host by number : He calleth 
them all by names, by the greatness of His might, for that He is 
strong in power ; not one faileth." Isa. 40 : 26. 

We have now to take flight in thought far, far 
beyond the outskirts of our little Solar System. 
Yes, our great Solar System, with its giant sun, 
its planets, its moons, its comets and meteors, its 
ceaseless motions, its vast distances — even all this 
sinks to littleness beside the wider reaches of 
space which now have to be pictured to our minds. 

For our sun, in all his greatness, is only a sin- 
gle star — only one star among other stars — and 
not by any means one of the largest of the stars. 

How many stars are there in the sky ? 

Look overhead some cloudless night and try to 
count the brilliant points of light. " Millions " 
you would most likely give as your idea of their 
number. Yet you would be wrong, for you do 
not really perceive so many. 

The stars visible to man's naked eye have 
been mapped and numbered. It is found that 



io6 Sun, Moon, and Stars. 

from two to three thousand are, as a rule, the ut- 
most ever seen at once, even on a favorable night 
and with particularly good sight. 

But what is actually the full number of the 
stars ? 

Two or three thousand overhead. Five or six 
thousand round the whole world. So much visible 
to man's unaided eyes. 

Ah, but take a telescope and see through it 
the opening fields of stars beyond stars. Take a 
stronger telescope, and note how, as you pierce 
deeper into space, fresh stars beyond fresh stars 
shine faintly in the measureless distances. Take 
the most powerful telescope ever made, and again 
it will be the same story. 

There has been a chart or map drawn of known 
stars in the northern hemisphere— including those 
visible in telescopes down to a certain magnitude — 
containing over three hundred thousand. But 
that is only a part of even what man can see. Sir 
W. Herschel reckoned that the stars within reach 
of his telescope, round the whole earth, amounted 
to twenty millions. With the largest modern tel- 
escopes the numbers perhaps amount to some- 
thing like sixty millions, perhaps to very many 
more. 



Neighboring Families. 107 

Sixty millions of suns ! For that is what it 
really means. Sixty millions of radiant shining 
heavenly bodies, some the same size as our sun, 
some larger, perhaps very much larger, some 
smaller, perhaps very much smaller, but all, or 
most of them, suns. And any of these suns may 
have, like our own, families of planets travel- 
ling round them, enjoying their light and their 
heat. 

We talk about stars of the first, second, and 
other magnitudes. Stars can be seen without a 
telescope as low down as the sixth magnitude ; 
after that they become invisible to the naked 
eye. 

This word " magnitude " is rather misleading. 
" Magnitude " means size, and whatever the real 
size of the stars may be, they have to our sight no 
seeming size at all. 

So when we speak of different magnitudes we 
really mean different brightnesses. The brightest 
stars are those of the first magnitude, the next 
brightest those of the second magnitude, and so 
on. No doubt many a star of the third or fourth 
magnitude is really much larger than many a 
star of the first or second magnitude, only being 



1 08 Sun, Moon, and Stars. 

farther away it shines more dimly, or the higher- 
magnitude star may in itself possess greater 
natural brilliancy. 

Of first-magnitude stars there are altogether 
about twenty ; of second-magnitude stars about 
sixty-five j of third-magnitude stars nearly two 
hundred ; and so the numbers increase, till of the 
sixth-magnitude stars we find more than three 
thousand. These are all that can be commonly 
seen with the naked eye, amounting to five or six 
thousand. With telescopes the numbers rise rap- 
idly to tens of thousands, hundreds of thousands, 
even millions and tens of millions. 

For a long while it was found quite impossible 
to measure the distances of the stars. To this 
day the distances of not over a hundred among all 
those tens of millions have been discovered. The 
difficulty of finding out the distance of the sun 
was as nothing compared with the difficulty of 
finding out the distances of the stars. 

No base-line sufficient for the purpose could for 
years be obtained. I must explain slightly what 
is meant by a " base-line.'' Suppose you were on 
the brink of a wide river which you had no means 
of crossing, though you wished to discover its 



Neighboring Families. 109 

breadth. Suppose there were on the opposite 
brink a small tree standing alone. As you stood 
you would see the tree seeming to lie against a 
certain part of the country beyond. Then if you 
moved along your bank some fifty paces you 
would see the tree still, but it would seem to lie 
against quite a different part of country be- 
yond. 

Now if you had a long piece of string to lay 
down along the fifty paces you walked, and if two 
more pieces of string were tied, one from each 
end of the fifty paces, both meeting at the tree, 
then the three pieces of string would make one 
large triangle, and the " fifty paces " would be the 
base of your triangle. 

If you could not cross the river you could not 
of course tie strings to the tree. 

But having found your base-line and measured 
its exact length, and having also found the shape 
of the two angles at its two ends, by noting the 
seeming change of the tree's position, it would 
then be quite easy to find out the distance of 
the tree. The exact manner in which this 
calculation is made can hardly be understood 
without some slight knowledge of a science 
called trigonometry. The tree's distance be- 



no Sun, Moon, and Stars. 

ing found, the breadth of the river would be 
known. 

This mode of measuring distance was found 
comparatively easy in the case of the moon. 

In the case of the sun there was more difficulty, 
on account of the sun's greater distance. No base- 
line of ordinary length would make the sun seem 
to change his position in the sky in the slightest 
degree. Nor till the very longest base-line on the 
earth was tried could the difficulty be overcome. 
That base-line is no less than eight thousand miles 
long. One man standing in England, looking at 
the sun, and another man standing in Australia, 
looking at the sun, have such a base-line lying 
between them, straight through the centre of the 
earth. 

In the case of the stars this plan was found use- 
less. So closely has the sky been mapped out, and 
so exactly is the place of each star known, that 
the tiniest change would have been at once 
noticed. Not a star showed the smallest move- 
ment. The eight thousand miles of the earth's 
diameter was a mere point with regard to 
them. 

A bright idea came up. Here was our earth 
travelling round the sun in an orbit so wide that 



Neighboring Families. 1 1 1 

in the middle of summer she is one hundred and 
eighty-five millions of miles away from where she 
is in mid- winter. Would not that make a magnifi- 
cent base-line ? Why not observe a star in sum- 
mer and observe the same star again in winter, 
and then calculate its distance ? 

This too was done. For a long while in vain ! 
The stars showed no signs of change beyond 
those due to causes already known. 

Astronomers persevered, however, and with 
close and earnest care and improved instruments 
success at last rewarded their efforts. A few — 
only a few, but still a few — of those distant suns 
have submitted to the little measuring line of 
earth, and their distance has been roughly calcu- 
lated. 

Now what is their distance ? 

Alpha Centauri, the second star which was at- 
tempted with success, is the nearest of all whose 
distance we know. 

You have heard how far the sun is from 
the earth. The distance of Alpha Centauri is 
two hundred and twenty-five thousand times as 
much. 

Can you picture to yourself that vast reach of 



H2 Sun, Moon, and Stars. 

space — a line ninety-two millions of miles long, 
repeated over and over again two hundred and 
twenty-five thousand times ? 

But Alpha Centauri is one of the very nearest. 
6 1 Cygni is five hundred thousand times as far as 
the sun, and Sirius nearly a million times. Oth- 
ers utterly refuse to show the smallest change of 
position. 

It is with them, as has been said, much the 
same as if a man were to look at a church stee- 
ple, twenty miles distant, out of one pane in a 
window, and then were to look at it out of the 
next pane. With the utmost attention he would 
find no change of position in the steeple. And 
like the base-line of two glass panes to that 
steeple, so is the base-line formed by our whole 
yearly journey to thousands of distant stars. We 
might measure how far away they are, only the 
longest base-line within our reach is too short for 
our purpose. 

The planet Neptune has a wider orbit than 
ours. But even his orbit, seen from the greater 
number of the stars, would shrink to a single 
point. 

After all, how useless to talk of two hundred 
thousand times ninety -two millions of miles! 



Neighboring Families. 113 

What does it mean? We cannot grasp the 
thought. 

Let us look at the matter from another view. 

Do you know how fast light travels — this 
bright light shining round us all day long? 
Light, so far as we know, does not exist every- 
where. It travels to and fro, from the sun to his 
planets, from the planets to one another, from the 
sun to the moon, from the moon to the earth, and 
from the earth to the moon again. 

Light takes time to travel. This sounds singu- 
lar, but it is true. Light cannot pass from place 
to place in no time. 

Light, journeying through space, is invisible. 
Only when it strikes upon something, whether a 
solid body or water or air, does it become visible 
to our eyes. The shining all round us in the day- 
time is caused by the sunlight being reflected, not 
only from the ground, but from each separate 
particle of air. If we had no atmosphere we 
should see still the bright rays falling on the 
ground, but the sky above would be black. Yet 
that black sky would be full of millions of light- 
rays journeying hither and thither from sun and 
stars, invisible except where they alight upon 
something. 

Sun, Moon, etc, 3 



1 1 4 Sun, Moon, and Stars. 

The speed of light is far beyond that of an 
express - train, far beyond that of the swiftest 
planet. Between two ticks of the clock Mercury- 
has rushed onward thirty-five miles. In the same 
space storm-flames uf)on the surface of the sun 
will sweep over two or three hundred miles. But 
in the same space a ray of light flashes through 
one hundred and eighty-six thousand three hun- 
dred miles. 

One hundred and eighty-six thousand miles! 
That is the same as to say that during one single 
instant a ray of light can journey a distance equal 
to about eight times round and round our whole 
earth at the equator. 

By using this wonderful light-speed as a meas- 
urement we gain clearer ideas about the distances 
of the stars. 

A ray of light takes more than eight minutes 
to pass from the sun to the earth. Look at your 
watch and note the exact time. See the hand 
moving slowly through the minutes, and imagine 
one single ray of light, which has left the sun 
when first you looked, flashing onward and on- 
ward through space, one hundred and eighty-six 
thousand miles each second. Eight minutes and 
three-quarters end. The ray falls upon your hand. 



Neighboring Families. 115 

In those few minutes it has journeyed ninety-two 
or ninety-three millions of miles. 

So much for the sun's distance. How about 
the stars ? 

Alpha Centauri, a bright star seen in the 
southern hemisphere, is one of our nearest neigh- 
bors. Yet each light-gleam which reaches the eye 
of man from that star left Alpha Centauri four 
years and four months before. During over four 
years, from the moment when first it quitted the 
surface of the blazing sun, it has flashed cease- 
lessly onward one hundred and eighty-six thou- 
sand miles each second, dwindling down with its 
bright companion-rays from a glare of brilliancy 
to a slender glimmer of light till it reaches the 
eye of mg,n. 

Four years and four months sounds much side 
by side with the nine minutes' journey from the 
sun. 

But look at 61 Cygni, distant somewhere about 
five hundred thousand times as far as the sun. 
The light of 61 Cygni takes more than seven 
years to reach the earth. 

Look at Sirius, that beautiful star so familiar 
to us all. The light which reaches you to-night 
from Sirius left his^ surface nearly nine years ago. 



1 1 6 Sun, Moon, and Stars. 

During the greater part of nine years that bright 
ray has been speeding onward and onward with 
ceaseless rapidity, till its vast journey is so 
far accomplished that it has arrived at our 
earth. 

Four — seven — nine years — at the rate of 186,- 
300 miles a second. 

These stars are among the few whose distances 
can be roughly measured. Little can be known 
with certainty about stars lying yet farther away. 
The light of a star of the third magnitude may 
perhaps take, on an average, fifty or sixty years to 
travel to us. Each lessening magnitude — more 
truly, each fainter light-gleam — means longer and 
longer journeys, except in occasional instances, 
where a larger and brighter sun is actually farther 
away than another more small and dim. The six- 
teenth-magnitude stars, just visible in the largest 
telescopes, may mean a light- journey from each 
of tens of thousands of years. But here, indeed, 
we are feeling our way in the dark. Others yet 
again may lie beyond in countless numbers, at 
measureless distances, all unknown to us. 

Through long centuries these star light-rays 
have been journeying onward, fulfilling incessantly 
their Maker's will. On that distant mission each 



Neighboring Families. 117 

ray started from the far-off sun which gave 
it birth — when ? There is solemnity in the 
thought. Hundreds of years ago. Thousands of 
years ago. Some maybe even tens of thousands 
of years ago ! It carries us out of the little pres- 
ent into the unknown ages of a past eternity- 



1 1 8 Sun, Moon, and Stars. 

CHAPTER X. 
OUR neighbors' movements. 

" Is not God in the height of heaven ? and behold the height 
of the stars, how high they are !" Job 22 : 12. 

How high ! how distant ! how mighty ! How 
little we know about them, yet how overwhelm- 
ing the little we know, and how wonderful must 
be our minds to be able to know it ! 

We have now to consider the movements of 
these distant neighbors — first, their seeming move- 
ments ; secondly, their real movements. 

I have already spoken about the seeming 
motions of the stars as a whole, once believed to 
be real and now known to be only caused by the 
motions of our earth. 

For just as the turning of the earth upon her 
axis makes the sun seem to rise every morning 
in the east and to set every evening in the west, 
so that same continued turning makes the stars 
seem to rise every evening in the east and to set 
every morning in the west. 

When we speak of the stars as rising in the 
east we do not mean that they all rise at one point 



Our Neighbors Movements. 119 

in the east, but that all rise, more or less, in an 
easterly direction — northeast, east, and southeast. 
So also with respect to the west. It is to the east 
and west of the earth as a whole that they rise 
and set — not merely to the east and west of that 
particular spot on earth where one man may be 
standing. 

All night long fresh stars are rising and others 
are setting ; and if it were not for the veil of light 
made by the sunshine in our atmosphere, we 
should see the same going on all day long as well. 

There are some constellations, or groups of 
stars, always visible at night in our northern hem- 
isphere ; and there are some constellations never 
visible to us, but only seen by people living in 
the southern hemisphere — in Australia for in- 
stance. 

There are other constellations which appear in 
summer and disappear in winter or which appear 
in winter and disappear in summer. This change 
is caused by our earth's journey round the sun, or, 
as in common language we express it, by the 
sun's journey round the earth. It is not that the 
constellations have altered their place in the 
heavens with respect to the other constellations : it 
is merely that the sun has so altered his position 



1 20 Sun, Moon, and Stars, 

in the heavens that the group of stars which a 
short time ago were above the horizon with him 
by day are now above the horizon without him by 
night. 

Mention has been a good many times made of 
the axis of the earth ending in the north and 
south poles. 

If this axis were carried straight onward 
through space, a long slender pole passing up- 
wards into the sky without any bend, from the 
North Pole in one direction and from the South 
Pole in the other, this would be the Pole of the 
heavens. The places of the stars in the sky are 
counted as " so many degrees " from the North 
and South Celestial Poles — just as the places of 
towns on earth are counted as " so many degrees " 
from the North and South Poles of earth. There 
are atlases of the sky made as well as atlases of 
the earth. 

The constellation of the Great Bear is known 
to all who have ever used their eyes at all to watch 
the heavens. Almost equally well known are the 
two bright stars in this constellation named the 
Pointers, because, taken together, they point in 
nearly a straight line to a certain important star 



Our Neighbors Movements. 121 

in the end of the Little Bear's tail, not very dis- 
tant. 

This star, important less from its brightness 
than from its position, lies close to that very spot 
in the heavens where the celestial North Pole 
passes. It is called the Pole-star. Night after 
night through the year it there remains, all but 
motionless, never going below the horizon for us 
in the northern hemisphere or northern half of 
the earth, never rising above the horizon for those 
in the southern hemisphere. It shines ever softly 
and steadily in its fixed position. If you travel 
further south, the Pole-star sinks downward to- 
wards the horizon. If you travel further north, the 
Pole-star rises higher above the horizon. If you 
were at the North Pole, you would see the Pole- 
star exactly overhead. 

Very near the Pole-star is the constellation of 
the Great Bear, with Cassiopeia nearly opposite 
on the other side of the Little Bear, and other 
groups between the two completing the circle. 
These constellations do not, to us who live in 
England, rise or set, for they simply move in a 
circle round and round the Pole-star, never going 
below the horizon. All day and all night long 
this circling movement continues, though only 



122 Sun, Moon, and Stars. 

visible at night. It is caused entirely by the 
earth's own motion on her axis. 

Lower down, or rather farther off from the 
Pole-star, comes another ring of constellations. 
These in just the same manner appear to travel 
round and round the Pole-star. But being far- 
ther away, each dips in turn below the horizon — or, 
as we call it, each sets and rises again. And by 
the time we come to yet another circle of leading 
constellations we reach those which are so far 
affected by the earth's yearly journey as to be only 
visible through certain months and to be hidden 
during other months. 

If we could stand exactly at the North Pole 
during part of its six months' night, we should 
see the Pole-star just overhead and all the con- 
stellations circling round it once in every twenty- 
four hours. Those nearest would move slowly, in 
a small ring. Those farthest, and lowest down, 
would in the same length of time sweep round 
the whole horizon. But the stars would not there 
seem to rise or set. 

If we were standing at the South Pole we 
should see exactly the same kind of seeming 
movement, only with altogether a different set of 
stars. 



Our Neighbors Movements. 123 

If we were standing on the Equator at night 
we should see the rising and setting very plainly. 
The whole mass of stars would appear to rise 
regularly and evenly in an easterly direction, to 
pass steadily across the sky, each taking its own 
straightforward path, and to set in a westerly 
direction. 

We in England, placed between the Pole and 
the Equator, see a mixture of these two motions. 
Some stars seem to circle round and round, as all 
would do if we stood at the North Pole. Some 
stars seem to rise and set, as all would do if we 
stood at the Equator. 

So much for the seeming movements of the 
stars. 

But now about their real movements. Are the 
stars fixed or are they not ? 

These seeming daily and yearly motions do 
not affect the question, being merely caused by 
our own motions. Trees and hedges may appear 
to move as we rush past them in a train, yet they 
are really fixed. 

During a long while, after it was found out 
that the quick daily movements of all the stars in 
company were merely apparent, men believed 



1 24 Sun, Moon, and Stars. 

that they really had no "proper motions," that is, 
no movements of their own. 

For century after century the constellations 
remain the same. Hundreds of years ago the 
seven chief stars of the Great Bear shone in com- 
pany as they shine now. Who could suppose that 
each one of those seven stars is hurrying on its 
path through space with a speed exceeding far 
that of the swiftest express-train? Yet so it is. 
Hundreds of years ago the grand group of Orion, 
with belt and sword, gleamed brilliantly night by 
night as it gleams in these days, and Cassiopeia 
had her W-form, and Hercules and Draco and 
Andromeda were shaped as they are shaped still. 
Who would imagine that through those hundreds 
of years each star of those different constellations 
was hastening with more or less of speed along its 
heavenly road ? Yet so it is. 

But if the stars are thus rapidly moving in all 
directions, how is it that we do not see them 
move ? How is it that night after night, year 
after year, century after century, even thousand 
years after thousand years, the shapes of the con- 
stellations remain unaltered ? 

Suppose you and I were standing on the sea- 
shore together, watching the movements of scores 



Our Neighbors Movements, 125 

of seacraft, little boats and large boats, steamers, 
yachts, and ships. Suppose we stood through a 
full quarter of an hour looking on. Some might 
move, it is true, very slowly, yet their movements 
in every case would plainly be seen. There could 
be no possibility of mistaking the fact or of sup- 
posing them to be " fixed. " 

Just so we see the nearer planets move. Little 
danger of our supposing them to be " fixed stars." 

In the matter of the stars themselves we must 
carry our illustration farther. 

Come with me up to the top of that lofty hill 
on the border of the sea and let us look from the 
cliff. We see still the movements among boats 
and smacks, yachts and steamers, only the in- 
creased distance makes the movements seem 
slower. 

But our view is widened. Look on the far 
horizon and see three distant dots, which we 
know to be ships — one and two close together 
and a third a little way off, making a small con- 
stellation of vessels. Watch them steadily for a 
quarter of an hour. You will detect no move- 
ment, no increased distance or nearness between 
any two of the three. The group remains un- 
changed. 



126 Sun, Moon, and Stars. 

Are they really moving ? Of course they are, 
more or less rapidly, probably with differing 
speed and in different directions. But at so great 
a distance one quarter of an hour is not long 
enough for their motions to become visible to the 
naked eye. If we could watch longer, say for two 
or three hours, ah, that would make all the differ- 
ence ! If only we could watch longer ! But the 
hundreds and even thousands of years during 
which men have watched the stars, sink, at our 
vast distance, into no more than one quarter of 
an hour spent in watching the far-off ships from 
the hill-top. The motions cannot be detected. 
In ten thousand years you might see something. 
In fifty thousand years you might see much. But 
four or five thousand years are not sufficient. 

One other mode there is by means of which 
the movements of the ships on the horizon might 
be made plain. Suppose you had no more than 
the quarter of an hour to spare, but suppose you 
had at your command a powerful telescope. Then 
you may practically bring the ships nearer, and 
by magnifying the small slow distant motions you 
may make them, as it were, larger, quicker, more 
easy to see. 

Telescopes will do this for us, likewise, in the 



Our Neighbors Movements. 127 

matter of the stars. By means of telescopes, with 
the assistance of careful watching and of close 
calculation, it has been found that the stars are 
really moving quickly, each one in his own path- 
way. The very speed of some of them has been 
measured. 

One fair star, Capella, speeds away from us at 
about the rate of one thousand miles each minute, 
or some sixteen or seventeen miles each second ; 
and the pale Pole-star, friend of mariners, is on 
the other hand advancing towards us no less rap- 
idly. The brilliant Sirius recedes at a pace of 
over twenty-six miles per second. There is good 
reason to believe that every star seen in the 
heavens, every star visible in most powerful tele- 
scopes, to the tune of millions, is incessantly has- 
tening onward. 

Hastening whither ? 

God knows ! We do not. Each radiant sun 
has its goal, but where that goal may be we 
cannot tell. Each doubtless has its own pathway 
around some distant centre — the centre of that 
Sun-cluster or Steller System or Starry Universe 
to which it belongs. Each follows its own path- 
way, controlled and regulated by the united attrac- 



128 Sun, Moon, and Stars. 

tions of all other suns belonging to the same Star- 
System : even as the planets of the Solar System 
are controlled by the central sun and influenced 
by each brother-planet. 

Yet it may be that not all the stars in our 
Stellar System are so controlled. Some few we 
know travelling at so vast a rate of speed as to 
have earned the title — whether rightly or wrong- 
ly — of " Runaway Stars." Sixteen miles, twenty 
miles, twenty-six miles per second sounds rapid 
enough ; but these rates are eclipsed. A certain 
dim double star, 61 Cygni, journeys at least twice 
as fast as Capella, or some thirty-six miles a sec- 
ond. This may still be a controlled speed, and 
6 1 Cygni c&n still be counted a permanent mem- 
ber of our System, subject to the restraint of 
brother-stars. 

But when we reach a certain degree of speed, 
then, it is conjectured, the power of this control 
may fail. One faint star, known as Groombridge 
1830, flies at the rate of over two hundred miles 
each second ; and Ar^turus, a brilliant star of the 
first magnitude, is believed to whirl along at the 
pace of three hundred and seventy-five miles each 
second. A star pursuing such a headlong career 
as either of the two last named, may — not improb- 



Our Neighbors Movements, 129 

ably — defy the combined control of all the other 
stars. Such stars are, perhaps, not members of our 
Stellar System, but passing visitors, entering from 
one direction, passing away in another direction. 

The thought of such bright suns, travelling 
through long ages from, far far distant Star-Sys- 
tems, entering our own, and during ages more 
journeying among our innumerable stars, only, 
in ages yet future, to pass away into depths of 
space beyond, perhaps to join some other starry 
universe — could aught be more full of suggestive- 
ness as to the meaning of Infinity? The life of 
mankind sinks to a point by comparison, the life 
of a man to the flutter of a May-fly. And whether 
or no the story of Runaway Stars be as thus pic- 
tured, such distances do exist ! 

If all the stars are moving, what of our sun ? 
Our sun is a star ! 

And our sun also is moving. He is pressing 
onward in a wide sweep through space, bearing 
along with him his whole family — planets, satel- 
lites, comets, meteors — round or towards some far- 
off centre, at a probable rate of sixteen or eigh- 
teen miles each second. 

Sun, Moon, etc. Q 



1 30 Sun, Moon, and Stars. 

And where are we going ? 

This has been in part discovered. 

If you and I were driving through a forest of 
trees, we should see trees on each side of us 
seeming to move backward, while behind they 
would close together and in front they would 
open out. 

Astronomers — and first among them William 
Herschel — reasoned that if our Solar System were 
really in motion we ought to be able to see these 
changes among the stars. And some such changes 
have become visible through careful watching — 
not so much those ahead and behind as those at 
the sides. 

It is not actually so simple a matter as looking 
at the trees in a forest, because the trees would 
be at rest, whereas each star has his own particu- 
lar real motion as well as his seeming change of 
place caused by our sun's motion. It is more like 
moving in a small steamer at sea among hun- 
dreds of other craft, each of which is going on its 
own way, at the same time that all on either side 
seem to move backward because we are moving 
forward. 

So each movement had to be noted, and the 
real motions had to be separated from the seem- 



Our Neighbors Movements. 1 3 1 

ing backward drift of stars to the right and left 
of the sun's pathway. The result of all this 
is that the sun, with his planets, is found to be 
hastening towards a certain far-off constellation 
named Hercules. 

Where the sun and his planets will journey 
in future ages no living man can say. Indeed, 
though it is a question which does not lack inter- 
est to a thoughtful mind, yet there are number- 
less other questions about centuries near at hand 
which concern man far more nearly. The history 
of the universe and the history of this earth of 
ours, in its close and wonderful connection with 
God and with Christ our Redeemer, must have 
advanced many broad stages before our sun and 
his attendant planets can have travelled so far 
that any change will be apparent in the shape of 
the star-constellations which spangle our sky. 



END OF PART I. 



PART II. 





Fig. i. — Total Eclipse of the Sun. 

The eclipse is total upon that portion of the Earth upon which the cone of dark- 
shadow falls ; and partial in the region of the lighter shade, or penumbra. 





Fig. 2. — Annular Eclipse of the Sun. 

The eclipse appears annular upon that portion of the Earth upon which the 
reversed dark cone of shadow falls. 





Fig. 3. — Partial Eclipse of the Sun. 





Fig. 4. — Total Eclipse of the Moon. 




Fig. 5. — Partial Eclipse of the Moon. 



tin, MOOW AHO S*A»6. 



More About the Solar System. 135 



CHAPTER I. 

MORE ABOUT THE SOLAR SYSTEM. 

" By the word of the Lord were the heavens made, and all 
the host of them by the breath of His mouth. . . . For He spake, 
and it was done; He commanded, and it stood fast."— Psa. 
33 : 6, 9. 

We have now reached a point where it ought 
not to be difficult for us to picture to ourselves 
with something of vividness the general outlines 
of the Solar System. 

A while ago this Solar System was a very sim- 
ple matter in the eyes of astronomers. There was 
the great sun fixed in the centre, with seven plan- 
ets circling round him — seven of course, it was 
said, since seven was the perfect number — and a 
few moons keeping pace with some of the planets, 
and an occasional comet, and a vast amount of 
black empty space. 

But astronomers now begin to understand bet- 
ter the wonderful richness of the System as a 
whole, the immense variety of the bodies contained 
in it, the perpetual rush and stir and whirl of life 



1 36 Sun, Moon, and Stars. 

in every part. Certainly there is no such thing as 
dull stagnation throughout the family. 

First we have the great blazing central sun ; 
not a sun at rest as regards the stars, but practical- 
ly at rest as regards his own system, of which he 
is always head and centre. Then come the four 
smaller planets, rapidly whirling round him, all 
journeying in the same direction and all having 
their oval pathways lying on nearly the same flat 
plane in space. Then the broad belt of busy little 
planetoids. Then the four giant planets, Jupiter 
nearly five times as far as our earth from the sun, 
Saturn nearly twice as far as Jupiter, Uranus nearly 
twice as far as Saturn, Neptune as far from Uranus 
as Uranus from Saturn, all keeping on very nearly 
the same level as the four inner planets. 

And between and about these principal mem- 
bers of the system, with their accompanying moons, 
we have thousands of comets flashing hither and 
thither with long radiant trains ; and myriads of 
meteorites, gathered often into dense vast herds or 
families, but also scattered thickly throughout 
every part of the system, each tiny ball reflecting 
the sun's rays with its little glimmer of light. 

Broad reaches of black and empty space ! 
Where are they ? Perhaps nowhere. We are very 



More About the Solar System. 137 

apt, in our ignorance, to imagine that where we 
see nothing there must of necessity be nothing. 

But for aught we know the whole Solar System, 
not to speak of sky-depths lying beyond, may 
gleam with reflecting-bodies great and small, from 
the great Jupiter down to the fine diamond-dust 
of countless meteorites. In this earth of ours we 
find no emptiness. Closer and closer examination 
with the microscope only shows tinier and yet 
tinier wonders of form and life, each perfect in 
finish. 

Not of form only, but of life. How about that 
matter as regards the Solar System ? Is our little 
world the one only spot in God's great universe 
which teems with life ? Are all other worlds mere 
barren empty wastes ? 

Surely not all ! So much at least we may safely 
surmise. Life of one kind or another probably 
either has been, or is, or will be at some future 
period, upon at all events some of the countless 
worlds existent in the universe. 

On the other hand we must remember that 
surmise is not certainty : and that we know, and 
can know, little or nothing about the matter. The 
many worlds of the Solar System ma}^ have been 
created for some widely different purpose, beyond 



1 38 Sun, Moon, and Stars. 

our present power to fathom or even to imagine. 
It is not necessary that every world should be 
formed for the one object of supporting life. It 
may even be, as has been suggested by one of the 
greatest astronomers of our day, that the other 
planets are but as " chips struck from the block* ' 
and flung aside, in the making of our world — a 
world by no means prominent in size or in weight 
or in radiance, and yet perhaps the greatest in the 
universe, because of the marvellous development 
of mind, and because of the extraordinary history 
of mankind, connected with it. 

The same reasoning may be used for the stars — 
those millions of suns lying beyond reach of man's 
unassisted eyes. Are they formed in vain? Do 
their beams pour uselessly into space, carrying light 
and warmth and life-giving power to nothing? 
But here again how little we know ! We stand on 
the shore of a boundless ocean, able to see but a 
little way, able to understand not a hundredth part 
of what we see ! That neither worlds nor suns 
are objectless or useless may be safely asserted, 
within certain limits ; but what the especial object 
and use of each bright orb may be we may not 
venture to assert — we can hardly venture even to 
conjecture. 



More About the Solar System. 139 

I have spoken of the probable fulness of the 
Solar System as a whole. We are so apt to think of 
things merely as we see them with our short sight 
that it is well sometimes to try to realize them as 
they actually are. 

Picture to yourself the great central sun pour- 
ing out in every direction his burning rays of 
light. A goodly abundance of them fall on our 
earth, yet the whole amount of light and heat 
received over the whole surface of this world is 
only the two-thousand-millionth part of the enor- 
mous amount which he lavishly pours abroad into 
space. 

How much of that whole is wasted ? None ; 
though, like other divine gifts in nature, light is 
given with a kingly profusion which knows no * 
bounds. Millions of rays are needed for the light- 
ing and nourishing and warming of our compan- 
ion-planets, while others are caught up by passing 
comets and myriads flash upon swift small me- 
teors. Of the rays so used many pass onward 
into the vast depths beyond our system, and dwin- 
dle down into dim star-like shining till they reach 
the far-off brother-stars of our sun. 

Have they aught to do there ? We cannot tell. 
We do not know how far the sun's influence reach- 



140 Sun, Moon, and Stars. 

es. As head and centre he reigns only in his own 
system. As a star among stars, a peer among his 
equals, he may, for aught we can tell, have other 
work to do. 

In an early chapter mention was made of the 
earth's three motions, two only being explained. 

First, she spins ceaselessly upon her axis. So 
does the sun and so do the planets. 

Secondly, she travels ceaselessly round and 
round the sun in her fixed orbit. So does each 
one of the planets. 

Thirdly, she journeys ceaselessly onward 
through space with the sun. So also do the rest 
of the planets. 

These last two movements, thought of together, 
make the earth's pathway rather perplexing at 
first sight. We talk of her orbit being an ellipse 
or oval ; but how can it be an ellipse if she is al- 
ways advancing in one direction ? 

The truth is the earth's orbit is and is not an 
ellipse. As regards her yearly journey around the 
sun, roughly speaking we may call it an ellipse ; as 
regards her movement in space, it certainly is not 
an ellipse. 

Think of the Solar System with the orbits of all 



More About the Solar System. 141 

the planets as lying nearly flat — in the manner 
that hoops might be laid upon a table, one within 
another. The asteroids, comets, and meteorites 
do not keep to the same level, but their light 
weight makes the matter of small import- 
ance. 

Having imagined the sun thus in the centre 
of a large table — a small ball, with several tiny 
balls travelling round him on the table at differ- 
ent distances — suppose the sun to rise slowly 
upwards, not directly up, but in a sharp slant, 
the whole body of planets continuing to travel 
round and at the same time rising steadily with 
him. 

By carefully considering this double move- 
ment you will see that the real motion of the 
earth — as also of each of the planets — is not a go- 
ing round on a flat surface to the same point from 
which she started, but is a corkscrew-like winding 
round and round upwards through space. Yet as 
regards the central sun the shape of the orbit 
comes very near being an ellipse, if calculated 
simply by the earth's distance from him at each 
point in turn of her pathway through the 
year. 

An illustration may help to explain this, On 



142 Sun, Moon, and Stars. 

the deck of a moving vessel you see a little boy 
walking steadily round and round the mast. 
Now is that child moving in a circle or is he 
not? 

Yes, he is. No, he is not. He walks in a cir- 
cle as regards the position of the mast, which re- 
mains always the centre of his pathway. But his 
movement in space is never a circle, since he con- 
stantly advances and does not once return to his 
starting-point. You see how the two facts are 
possible side by side. Being carried forward by 
the ship, with no effort of his own, the forward 
motion does not interfere with the circling mo- 
tion. Each is performed independently of the 
other. 

It is the same with the earth and the planets. 
The sun, by force of his mighty attraction, bears 
them along wherever he goes, no exertion on 
their part, so to speak, being needed. That mo- 
tion does not in the least interfere with their 
steady circling round the sun. 

Just as — to use another illustration — the earth, 
turning on her axis, bears through space a man 
standing on the equator at the rate of one thou- 
sand miles an hour. But this uniform movement, 
unfelt by himself, does not prevent his walking 



Illillliliiil'S 1 :;!!!!!!!! 







More About the Solar System. 143 

backwards or forwards or in circles as much as he 
will. 

So also a bird in the air is unconsciously borne 
along with the atmosphere, yet his freedom to 
wheel in circles for any length of time is un- 
touched. 

A few words about the orbits of the planets. 

I have more than once remarked that these 
pathways are in shape not circles, but ellipses. A 
circle is a line drawn in the shape of a ring, every 
part of which is at exactly the same distance from 
the centre-point or focus. But an ellipse, instead 
of being like a circle perfectly round, is oval in 
shape ; and instead of having only one focus, it 
has two foci, neither being exactly in the centre. 
Foci is the plural word for focus. If an ellipse is 
only slightly oval — or slightly elliptical — the two 
foci are near together. The more oval or eccen- 
tric the ellipse, the farther apart are the two 
foci. 

You may draw a circle in this manner. Lay a 
sheet of white paper on a board and fix a pin 
through the paper into the board. Then pass a 
loop of thread — say an inch or an inch and a half 
in length — round the pin, and also round a pencil, 



144 Sun, Moon, and Stars. 

which you hold. Trace a line with the pencil, 
keeping the loop tight, so that the distance of 
your line from the pin will be always equal, and 
when it joins you have a circle. The pin in the 
centre is the focus of the circle. 

To draw an ellipse you must fix two pins. Let 
them be about half an inch apart ; pass a loop over 
both of them, and again placing a pencil-point 
within the loop, again trace a line carefully all 
round, keeping the thread drawn tight. This 
time an oval instead of a circle will appear. By 
putting the pins nearer together or farther apart 
you may vary as you will the shape of the 
ellipse. 

In the orbits of the earth and the planets, all 
of which are ellipses in shape, the sun is not 
placed in the exact centre, but in one of the two 
foci, the second being empty. So at one time of 
the year the planet is nearer to the sun than at 
another time. Our earth is no less than three 
millions of miles nearer in winter than she is in 
summer — speaking of the winter and summer of 
the northern hemisphere. Three millions of miles 
is so tiny a piece out of ninety-two millions of 
miles that it makes little or no difference in our 
feelings of heat or cold. 



More About the Solar System. 145 

The orbits of some comets are ellipses also, but 
ellipses often so enormously lengthened out that 
the two foci are almost — if one may so speak — at 
the two ends of the oval. To draw a good comet 
orbit you must fix the two pins on your paper 
some five or six inches apart, with a loop of thread 
just large enough to slip over them both and to 
allow the pencil to pass round them. When your 
ellipse is drawn you must picture the sun in the 
place of one of the two pins, and you will see how 
in their pathways the comets at one time pass 
very near the sun and at another time travel very 
far away from him. 

It is generally found in families not only that 
the parent or head of the family has great in- 
fluence over all the members, but that each mem- 
ber has influence over each other member. Bro- 
ther influences brother, and sister influences 
sister. 

This, too, we find in the Solar System. 

Not only does the sun by his powerful attrac- 
tion bind the whole family together, but each 
member of the family attracts each other 
member. 

True, the force of the sun's attraction is over- 
powering in amount compared with others. The 

Sun, Moon, etc. IQ 



146 Sun, Moon, a7td Stars. 

sun attracts the planets and the planets attract 
the sun ; but their feeble pulling is quite lost in 
the display of his tremendous strength. 

Among themselves we see the power more 
plainly. The earth attracts the moon, keeping 
her in constant close attendance ; and the moon 
attracts the earth, causing a slight movement on 
her part, and also causing the tides of the sea. 
Each planet has more or less power to hinder or 
help forward his nearest brother-planet. For in- 
stance, when Jupiter on his orbit draws near the 
slower Saturn on his orbit, Saturn's attraction 
pulls him on and makes him move faster than 
usual ; but as soon as he gets ahead of Saturn, 
then the same attraction pulls him back and 
makes him go more slowly than usual. Jupiter 
has the same influence over Saturn ; and so also 
have Saturn and Uranus over one another, or 
Uranus and Neptune. 

In early days astronomers were often greatly 
puzzled by these quickened and slackened move- 
ments, which could not be explained. Now the 
" perturbations'' of the planets, as they are called, 
are understood and allowed for in all calcula- 
tions. 

Indeed it is by means of this very attraction 



More About the Solar System. 147 

that the planets have actually been weighed, 
somewhat in the same manner — to illustrate it 
roughly — as one might test the weight of two 
strong children, by setting each to pull against 
the other and seeing which could pull the hardest. 

What a wonderful difference we find in this 
picture of the Solar System as we now know it to 
be from the old-world notion of our earth as the 
centre of the universe ! 

When we think of all the planets, and of the 
magnificent sun, when we pass onward in imagi- 
nation through space, and find our sun himself 
merely one twinkling star amid the myriads of 
twinkling stars scattered broadcast through the 
heavens, while planets and comets have sunk to 
nothing in the far distance, then indeed we begin 
to realize the unutterable might of God's power! 
Why, our earth and all that it contains may be 
regarded as but one grain of dust in the wide 
universe. 

And yet — 

Is there " great" and is there " little" intrinsi- 
cally ? We do not know. Probably not, as we see 
either. The might of God is no less shown in the 
exquisite finish of a flower or an insect than in 



148 Sun, Moon, and Stars. 

the fierce radiance of the stars. And, little 
though our earth may be, it was not too small or 
too unimportant for the kingly Creator himself to 
dwell here for over thirty years and here to 
redeem with his life the life of man. F6r not 
even in one corner of his boundless universe 
might evil be left to reign unconquered. 




The Moon. 



Sun, Moon and Stars, 



p. 148. 



More About the Sun. 149 



CHAPTER II. 



MORE ABOUT THE SUN. 



"He is wise in heart and mighty in strength ; . . . which 
doeth great things past rinding out ; yea, and wonders without 
number." — Job 9:4, 10. 

Not among the least of the wondrous things 
of creation are the tremendous disturbances ta- 
king place upon the surface of the sun — that 
raging roaring sea of flame. 

A good many explanations have been from 
time to time offered as to the dark spots seen to 
move across the face of the sun. Some one or 
more of these explanations may be true, but a 
great deal of uncertainty still exists. 

A sun - spot does not commonly consist of 
merely one black patch. There is the dark centre 
called the umbra — plural, umbra. There is the 
grayish part surrounding the umbra, called the 
penumbra. Also, in the centre of the umbra, 
there is sometimes observable an intensely black 
spot called the nucleus. 

* Sometimes a spot is made up of nucleus and 



1 50 Sun, Moon, and Stars. 

umbra alone, without any penumbra. Sometimes 
it is made of penumbra alone, without any umbra. 
Sometimes in one spot there are several umbrae, 
with the gray penumbra round the whole and gray 
bridges dividing the umbrae. 

The enormous size of these spots has been 
already described in an earlier chapter. Fifty 
thousand to one hundred thousand miles across is 
nothing unusual. In the year 1873 a spot was 
seen five times as large as the whole land and 
water surface of the earth. 

One explanation proposed was that the sun 
might be a cool body covered over with different 
envelopes or dense layers of cloudy form, one 
above another. The inside envelope, or as some 
say the inside atmosphere, would then be thick 
and dull-colored, protecting the solid globe within, 
and reflecting light, but having none of its own. 
The next envelope would be one mass of raging 
burning gases— the photosphere, in fact. The outer 
envelope would be a transparent surrounding 
atmosphere lighted up by the sea of fire within. 
A sun-spot would then consist of the tearing open 
of one or more of these envelopes so as to give 
glimpses of the gray inner atmosphere, or even of 
the dark cool globe at the centre. 



More About the Sun. 151 

There can be little truth in this explanation, 
since the notion of a cool and dark body within is 
now pretty well given tip. The apparent black- 
ness of a spot-nucleus does not prove actual black- 
ness or absence of heat. A piece of white-hot iron 
held up against the sun looks black ; and it may 
be merely the contrast of the glowing photosphere 
which makes the nucleus seem so dark. It is even 
believed that the blackest parts may be the most 
intensely hot of all. 

Another proposed explanation was of dark 
clouds floating in the sun's atmosphere. But 
since the whole photosphere is now believed to 
consist of bright clouds floating in the solar atmo- 
sphere, this theory too has gone to the wall. 

Much doubt is felt whether the spots really are 
depressions at all, although they certainly have 
often the appearance of a hollow and cave-like 
form. 

Beside apparent changes of shape, caused by 
changes of position as the spots travel across the 
sun's face, there are also real changes constantly 
taking place. Although the spots often keep their 
general outlines long enough to be watched across 
the face of the sun, and even to be known again 
after spending nearly a fortnight hidden on the 



152 Sun, Moon, and Stars. 

other side, still they are far from being fixed in 
form. 

The alterations are at times not only very great 
but very rapid. Sometimes in a single hour of 
watching an astronomer can see marked move- 
ment going on — as you or I might in an hour 
observe movements slowly taking place in a high 
layer of clouds. For movement to show at all in 
one hour, at so immense a distance, proves that 
the actual rate of motion must be very great. 

Whatever else we know or do not know about 
the spots, it seems probable that they are caused 
by some description of cyclones on the sun's sur- 
face. A cyclone is a fierce hurricane of wind 
blowing round and round in a circle — a whirlwind 
on a large scale. 

These sun-cyclones must indeed be of terrific 
force and extent, viewed side by side with any- 
thing that we see on our earth. The speed of 
movement perceived in some spots has been cal- 
culated to amount to no less than one and two 
hundred miles or more each second. The most 
violent hurricanes of earth sink by comparison 
into nothing. 

Sometimes the storms or outbursts come in 



More About the Sun. 153 

the shape of a bright spot instead of a dark 
one. 

Two astronomers were one day watching the 
sun from two different observatories when they 
saw such an event take place. An intense and 
dazzling spot of light burst out upon the surface 
of the sun — so intense, so dazzling, as to stand 
quite apart from the radiant photosphere. To 
one astronomer it looked like a single spot, while 
the other saw two spots close together. In about 
a minute the light grew more dim, and in five 
minutes all was over. But in those five minutes 
the spot or spots had travelled a distance of thirty- 
five thousand miles. 

It was a notable matter that the magnets on 
earth — those delicate little needles which point so 
steadily and perse veringly towards the North 
Pole — seemed to be strongly agitated by the dis- 
tant solar outburst. 

This brings us to another interesting fact. 

The spots on the sun are not always the same 
in number. Sometimes they are many, sometimes 
they are few. Long and close watching has made 
it clear that they pass through a regular order of 
changes, some years of many spots being followed 
by other years of less and less spots ; then some 



154 Sun, Moon, and Stars. 

years of very few spots being followed by other 
years of more and more spots, decrease and in- 
crease being seemingly regular and alternate. 

This turn or cycle of changes, from more to less 
and then from less to more again, is found to run 
its course about once in every eleven years, with 
some variations. 

Now it has long been known that the magnetic 
needle goes through curious variations. Though 
we speak of it as pointing always north, yet it 
does not always so point exactly. 

Every day the needle is found to make certain 
tiny delicate motions, as if faintly struggling to 
follow the daily movements of the sun — just a lit- 
tle towards the east or just a little towards the 
west. These tiny motions, having been long 
watched and measured, were found to go through 
a regular course of changes— some years more 
and some years less, waxing and waning by turns. 
It was discovered that the course of changes from 
more to less, and from less to more again, took 
place in about eleven years. 

These two things, you see, were quite indepen- 
dent of one another, Those who watched the 
sun-spots were not thinking of the magnets, and 
those who watched the magnets were not thinking 



More About the Sun. 155 

of the sun-spots. But somebody did at last happen 
to think of both together. He was laughed at, 
yet he took the trouble carefully to compare the 
two. 

And, very remarkably, he found that these 
two periods in the main agreed — the eleven years 
of alternate changes in the number of sun-spots 
and the eleven years of alternate changes in the 
movements of the magnetic needle. When the 
spots are most the needle moves most. When the 
spots are least the needle moves least. 

So much we know. But to explain the why 
and the wherefore is beyond our power. 

There is a very singular appearance seen upon 
the sun which must not be passed over without 
mention. 

Some astronomers speak of the whole surface 
as being mottled all over with a curious rough look 
when examined through a powerful telescope. 

This " mottling " is described by various ob- 
servers in various ways. One speaks of " luminous 
spots shaped like rice-grains ;" another of " lumi- 
nous spots resembling strokes made with a cam- 
el's hair pencil ;" another of " luminous objects or 
granules ;" others of " multitudes of leaves," " nod- 



156 Sun, Moon, and Stars, 

tiles," " crystalline shapes," " leaves or scales cross- 
ing one another in all directions, like what are 
called spills in the game of spillikins." They have 
also been pictured as " certain luminous objects of 
an exceedingly definite shape and generaj uni- 
formity of size, whose form is that of the oblong 
leaves of a willow-tree. These cover the whole 
disc of the sun, excepting the space occupied by 
the spots, in countless millions, and lie crossing 
each other in every imaginable direction." 

In size they are said to be about one thousand 
miles long by two or three hundred broad, but 
they vary a good deal. Where there is a spot the 
willow-leaves at its edge are said to point pretty 
regularly towards the centre. 

"It would appear," writes astronomer - royal 
Ball, alluding to these objects, "as if the luminous 
surface of the sun was composed of intensely 
bright clouds suspended in a darker atmosphere. 
Some observers have thought that these floating 
objects are, occasionally at all events, of a charac- 
teristic size and shape, variously known as ' wil- 
low leaves ' or ' rice granules !' " 

We have next to think a little more about the 
edge or limb of the sun and the stormy flames and 
outbursts there seen. 



More About the Sun. 157 

Until of late years the only time for observing 
such appearances was during a total eclipse of 
the sun. Now, however, by means of the " spec- 
troscope " it has been found possible to take ob- 
servations when no eclipse is going on. 

A few words of explanation as to eclipses of 
the sun seem needful before going farther. 

An eclipse of the sun is caused simply by the 
round body of the moon passing exactly between 
the sun and the earth so as to hide the sun from 
us. 

Let there be a candle on the table, while you 
stand near. The rays of light from the candle fall 
upon your face. Now move slowly, to and fro, a 
round ball between you and the candle. So long 
as it is not precisely in the line between — so long 
as it is a little higher or a little lower or a little to 
one side — then you can see the flame. Once let 
the ball come just between the light and your 
eyes, and you see it no more. In other words the 
candle-flame is eclipsed by the ball. 

It msiy seem curious at first sight that the 
moon, which is so very small compared with the 
sun, should have power to cover the sun. But 
remember the difference of the distances. The 



158 Sun, Moon, and Stars. 

sun is very far and the moon is very near. Any 
small object very near will easily hide from your 
sight a large object at a considerable distance. 
You may hold up a shilling-piece at arm's length 
and make it cover from sight a man, or even a 
house, if the latter be far enough away. 

The sun at a distance of ninety-two millions of 
miles, and the moon at a distance of two hundred 
and forty thousand miles, have to our vision the 
same seeming size. So, when the moon glides 
between, her round face just about covers the 
sun's round face. 

If the moon were travelling exactly in the 
same plane as the plane of the earth's orbit, an 
eclipse would be a very common affair indeed. 
But the plane of the moon's orbit being not quite 
the same as the plane of the earth's orbit, she 
passes sometimes a little above and sometimes a 
little below the exact spot where she would hide 
the sun's rays from us. Now and then, at certain 
intervals, she goes just between. And so well is 
the moon's path in the heavens understood that 
astronomers can tell us long years beforehand in 
what day and at what hour an eclipse is certain 
to take place. 

An eclipse of the sun is sometimes partial, 



More About the Sun. 159 

sometimes total, sometimes annular. In a partial 
eclipse the moon does indeed pass between, but 
only so as to hide from us part of the sun. She is 
a little too low or a little too high to cover his face. 
In a total eclipse the moon covers the sun com- 
pletely, so that for a few minutes the bright 
photosphere seems blotted out from the heavens, 
a black round body surrounded by light taking 
its place. In an annular eclipse the moon in like 
manner crosses the sun, but does not succeed in 
covering him entirely, a rim of bright photo- 
sphere showing round the black moon. For in an 
annular eclipse the moon, being a little farther 
away from the earth than at the time of a total 
eclipse, has too small a disc quite to hide the sun's 
disc. 

The blackness of the moon during an eclipse 
is caused by the fact that her bright side is turned 
towards the sun and her dark side towards us. An 
eclipse of the sun can only take place at new 
moon,* never at full moon. At her full the moon 

* A peculiar interest belongs to this fact. For while our 
Lord hung upon the cross there came a strange and mysterious 
darkness over the whole land for three hours. Now it might be 
supposed that this darkness was caused by an eclipse of the 
sun — but no such eclipse can ever take place except at new moon, 



1 60 Sun, Moon, and Stars. 

is outside the earth's orbit, away from the sun, 
and cannot by any possibility pass between. 

Eclipses of the sun in olden days were a source 
of wide-spread awe and terror. Many wild tales 
and wilder explanations were invented to account 
for them. Now that we better understand their 
meaning, fear need no longer be felt, though the 
strange darkness and the singular coloring of sky 
and air must always be exceedingly impressive. 

The following description of the total eclipse 
of i860 will be found interesting. It was ob- 
served by several astronomers who stationed them- 
selves at various places in the north of Spain — Mr. 
Airy, the Astronomer-Royal, at Pobes ; M. Bruhns 
of Leipzic, near Tarragona ; Mr. Lowe, near San- 
tander. Mr. Lowe writes : 

" Before totality commenced the colors in the 

sky and on the hills were magnificent beyond all 

description. The clear sky in the north assumed 

a deep indig'o color, while in the west the horizon 

was first black like night. In the east the clear 

sky was very pale blue, with orange and red like 

sunrise. On the shadow sweeping across, the 

deep blue in the north changed like magic to 

nor for more than six minutes ; and the Feast of the Passover, 
when He was crucified, always took place at the full moon. 



More About the Sun. 161 

pale sunrise tints of orange and red, while the sun- 
rise appearance in the east had changed to indi- 
go. The darkness was great ; the countenances of 
men were of a livid pink. The Spaniards lay 
down, and their children screamed with fear; 
fowls hastened to roost, ducks clustered together, 
pigeons dashed against the houses, flowers closed, 
many butterflies flew as if drunk and at last dis- 
appeared. The air became very humid, so much 
so that the grass felt to one of the observers as if 
recently rained upon."'* 

* From " Descriptive Astronomy," by G. F. Chambers. 



Sun, Moon., etc. 1 1 



1 62 Sun, Moon, and Stars. 

CHAPTER III. 

YET MORE ABOUT THE SUN. 
" O Lord, how great are thy works !" Psa. 92 : 5. 

Having seen something of storms taking place 
on the sun's photosphere, we must next give our 
attention to storms taking place at his edge. 
But it should be remembered that the said edge, 
far from beitig a mere rim to a flat surface, is a 
kind of horizon-line — is in fact just that part of 
the photosphere which is passing out of or coming 
under our sight. The surface there is in kind the 
same as the surface of the broad disc facing us. 
In watching outbursts at the edge of the sun we 
have a side-view instead of a bird's-eye view. 

In the year 1871 an American astronomer, 
Prof. Young, was looking at a large hydrogen 
cloud on the edge of the sun. When I speak of 
a " cloud " it must not be supposed that anything 
like a damp foggy earthly cloud is meant. This 
solar cloud was a huge mass of glowing gas about 
one hundred thousand miles long, rising to a 
height of fifty thousand miles from the sun's 
surface and appearing to rest on pillars of fire. 



Yet- More About the Sun. 163 

The professor, while watching, was called 
away for half an hour. He came back expecting 
to find things much as he had left them. Instead 
of this a startling change had taken place. The 
whole mass of crimson fire seemed to have been 
actually " blown to shreds" by some tremendous 
outburst from below. In place of the motionless 
cloud were masses of scattered fire, each from 
about four thousand to fourteen thousand miles 
long and a thousand miles wide. 

As the professor gazed, these " bits " of broken 
cloud rose rapidly upwards, away from the surface 
of the sun. When I say " rapidly," I mean that 
the real movement, which the professor could cal- 
culate, was rapid. The seeming movements were 
of course slow and over a small space. The actual 
motions were not tardy, for in ten minutes these 
huge fiery cloud-pieces rushed upwards to a height 
of two hundred thousand miles from the edge of 
the sun, moving at a rate of at least one hundred 
and sixty-seven miles each second. Gradually 
they faded away. 

But what caused this sudden change ? 

Just before the professor was interrupted he 
had noticed a curious little brilliant lump — a sort 
of suspicious thunder-cloud appearance — below the 



1 64 Sun, Moon, and Stars, 

quiet bright cloud. And after this tremendous 
shattering the little bright lump rose upwards 
into a huge mass of rolling flame, reaching like a 
pyramid to a height of fifty thousand miles. In 
the course of a few minutes these enormous flames 
could be seen to move and bend and to curl over 
their gigantic tips. But they did not last long. 
At half-past twelve the professor had been called 
away ; by half-past two the rolling flames com- 
pletely vanished. 

Now, whatever may be the full explanation of 
this sight, there is no doubt that on that day was 
observed from earth a gigantic outburst, compared 
with which our greatest volcanoes are like the 
sputtering of a farthing dip beside a roaring fur- 
nace. The awful force and extent of such a solar 
eruption are more than we can possibly picture to 
ourselves. At our distance we may catch a faint 
glimpse of what is going on and calculate speed of 
movement. But vividly to realize the actual ter- 
rific grandeur of what took place is past our 
power. 

Possibly this was much the same kind of out- 
burst as that seen by the two English astronomers ; 
only theirs was a bird's-eye view, as it were, look- 
ing down on the top of the sight, while the profes- 




■flip* 




Yet More About the Sun. 165 

sor had a side-view, certainly much the best for 
observation. 

It does not follow from what he saw that the 
eruption must have taken place exactly at the 
"edge" of the sun. Probably it happened near 
the edge. All he could say was that the flames 
rose fifty thousand miles, and the pieces of cloud 
were carried two hundred thousand miles, away 
from the edge. The eruption may have begun 
on the other side of the sun, at any distance from 
the horizon-edge where it first became visible to 
earthly eyes. 

Also, while the professor found that the shat- 
tered cloudlets moved at a rate of about one hun- 
dred and sixty-seven miles each second, it is cal- 
culated that the first fearful outburst must have 
caused movement near the surface of the sun at a 
rate of at least three hundred miles each second. 
Probably the hydrogen cloud was borne upwards 
along with a vast mass of fragments flung out 
from the sun. We are here upon doubtful ground ; 
but this stupendous power of eruption in the sun, 
and of driving matter out of and away from his 
surface, should not be forgotten. 

Though such a sun-storm as that just described 



1 66 Sun, Moon, and Stars. 

is not often to be seen, yet there are at all times 
certain strange red prominences, or glowing flames, 
rising tip here and there from the sun's " limb/' 
Doubtless they rise also from other parts of the 
photosphere, though they are only visible to us 
when near enough to the edge to stand out be- 
yond it. 

As generally seen, these prominences have 
clear sharp outlines and are usually bright rose-red 
in color. They are described as sometimes wide 
and low, sometimes tall and slender ; sometimes 
jagged, sometimes regular ; sometimes keeping 
long the same shape, sometimes changing quickly 
in a few minutes. They are said to be like flames, 
like mountains, like the teeth of a saw, like ice- 
bergs, like floating cloudlets. 

As to their height, from fifty to eighty thou- 
sand miles is nothing unusual. We must not 
speak of Mont Blanc or Mt. Everest here. Jupi- 
ter, placed bodily on the surface of the sun beside 
such a fire-mountain, would not far overtop it. 
The earth, Venus, Mars, and Mercury would lie 
like little toy-balls at its foot. And these are com- 
mon-sized sun-flames. One has been measured 
which reached one hundred and sixty thousand 
miles in height, and even this has been exceeded. 



Yet More About the Sun, 167 

The spectroscope shows these solar prominen- 
ces or jets to be principally formed of glowing hy- 
drogen gas. 

Beyond the sierra or chromatosphere — that 
border of rippling crimson fiery billows round the 
edge of the sun, with tall red mountains rising out 
of it here and there — beyond these stretches the 
corona. 

The corona, as seen from earth, is a bright far- 
reaching glory of light shining round the sun in a 
total eclipse. The moon then comes between the 
sun and the earth, her dark round body creeping 
over the face of the sun till the bright photosphere 
is completely covered. But the sierra and the red 
prominences stand out from behind the black 
moon, and the beautiful soft corona light stretches 
far beyond. 

It was long doubted whether the corona really 
belonged to the sun or to the moon. No question 
now exists that it is a part of the sun. 

Various descriptions of the corona have been 
given at different times as observed during differ- 
ent eclipses. It has been seen as a steady beamy 
white cloud behind the moon, showing no flicker- 
ing. It has been seen marked with bright lines 



1 68 Sun> Moon, and Stars. 

of light and seeming to move rapidly round and 
round. It has been seen silvery white, sending 
off long streams of brightness. It has been seen 
in the form of white light, with bluish rays run- 
ning over it. It has been seen with entangled 
jets of light, like "a hank of thread in disorder." 
It has been seen silvery white again, with a faint 
tinge of greenish- violet about the outer edge. It 
has been seen from a high#mountain-top as a mass 
of soft bright light, " through which shot out, as 
if from the circumference of the moon, straight 
massive silvery rays, seeming distinct and separate 
from each other, to a distance of two or three 
diameters of the lunar disc, the wimple spectacle 
showing as upon a background of diffused rose- 
colored light." 

The shape of the corona seems to change much 
at different times ; and the outer edge is blurred 
and indistinct, fading imperceptibly away. How 
far it reaches, in a state of extreme thinness, no 
one can tell. Outlying portions, which the strong- 
est sight cannot detect in the most powerful tele- 
scope, can be pictured by means of photography. 

Different explanations of this crown of light 
have been suggested. Some suppose it to consist 
of an atmosphere, gaseous in kind, reaching out- 



Yet More Abo^tt the Sun. 169 

ward from the sun's surface, growing ever more 
and more rare, after the fashion of our own atmo- 
sphere, only to an inconceivably greater extent. 
Some have conjectured it to be formed of count- 
less revolving " meteorite particles," more after 
the fashion of Saturn's rings. But our knowledge 
of the true nature of the corona is yet in its in- 
fancy. 

A few closing words as to the size and weight 
of the sun. 

In diameter eight hundred and sixty thousand 
miles, and in bulk equal to over one million two 
hundred thousand earths, his weight is in propor- 
tion less. 

Our earth is about four times as dense as the 
sun. If her size w^ere increased to the sun's size, 
her density being the same as now, she would be 
very much heavier than the sun and would attract 
much more strongly. 

Still, though the sun is of lighter materials 
than the earth, his immense size gives him weight 
equal to seven hundred and fifty times as much as 
all the planets put together. 

The attraction on the surface of the sun is also 
very great — so great that we can hardly picture it 
to ourselves. If life exists there at all — supposing 



1 70 Sun, Moon, and Stars. 

it possible that any kind of life can be in such a 
fiery atmosphere — it must be life very different 
from any known in this world. 

A man who on earth weighs twelve or fourteen 
stone and walks lightly erect, would on the sun lie 
helplessly bound to the ground, crushed by his 
own overpowering weight. 

It is said that a cannon-ball reposing on the 
sun, if lifted one inch and allowed to fall, would 
dash against the ground with a speed three times 
greater than that of our fastest express-trains. 

For weight on earth is merely caused by the 
amount of force with which the earth draws down- 
ward a body towards herself — a force greater or 
less according to the density of that body. So 
weight on the sun would be immensely increased 
by his immensely greater power of attraction. 

It is an interesting question how far the sun's 
attractive influence reaches effectually through 
space. The nearer a body is to the sun, the 
greater the attraction which he exercises over it. 

At the distance of the planet Mercury a speed 
of some thirty miles each second is needful to 
overcome or balance it sufficiently for the planet 
to remain in his orbit. At the distance of the 
planet Neptune about four miles each second is 



Yet More About the Sun. 1 7 1 

enough. If a planet were journeying at four 
times the distance of Neptune, the speed would 
need to be not over two miles each second, lest 
the planet should break loose and wander away. 

But even two miles a second is no mean speed — 
more than seven thousand miles an hour. If we 
come to speak of that which we on earth call rapid 
motion, we shall gain a clearer idea as to the ex- 
tent of the sun's power. 

Suppose a planet were travelling through space 
at the rate of one of our express-trains — sixty 
miles an hour. It has been calculated that, unless 
the sun's attraction were interfered with and over- 
powered by some nearer sun — which, by the way, 
would probably be the case — the said planet, 
though placed at a distance ten or twelve times as 
great as that of the far-off star Alpha Centauri, 
would still be forced by the sun's attraction to 
journey round him in a closed orbit. At such a 
speed it would not be free to wander off into the 
depths of space. 



1 7 2 Sun, Moon, and Stars. 

CHAPTER IV. 

MORE ABOUT THE MOON. 

" When I consider . . . the moon . . . which Thou hast or- 
dained."— Psa. 8 : 3. 

From a globe all fire, all energy, all action, we 
come to a globe silent, voiceless, changeless, life- 
less. 

So, at least, the moon seems to us. But it does 
not do to speak too confidently. 

True, we can find no trace of an atmosphere in 
the moon. If there is any atmosphere at all, it 
must be so thin as to be less than that which we 
on earth count as actually none. We pump away 
the air from a glass inclosure, in an air-pump, and 
say the glass is empty. 

Only it is not absolutely empty. There is 
always a very little air remaining ; merely a few 
stray particles, perhaps, so little that fire would 
not burn and animals could not live in it. Very 
possibly air to that amount may still cling to the 
moon ; but this is much the same as to say that no 
air at all is there. At all events, it is far too little 
to support life. 



More About the Moon. 173 

The question of the lunar atmosphere is full of 
interest. Many theories have been started to 
account for its absence ; and most of these, sooner 
or later, have had to be given up. 

Of late a singular thought has come to the 
front — that the moon very likely had once an 
atmosphere, like other worlds, but that in course 
of time she lost it as a matter of necessity. 

Why should she ? 

Because she was too small to keep it. 
Something may certainly be said in support of 
this view. An atmosphere is made of gases ; and 
the tiny particles of a gas are in swift and cease- 
less motion, fighting to get as far off one from 
another as possible. Such motion would carry the 
particles of every gas away from every planet and 
sun, except for the restraint of gravitation. As 
our earth by the force of attraction holds down 
her atmosphere, so do other celestial bodies. 

But if a world be very small, then its attraction 
is weak, too weak, it may be, for the control of 
those swift gas particles. In such a case the atmo- 
sphere might be expected, in the course of years, 
slowly to break loose, particle by particle, melting 
away into distant space. 

This may have been the case with our moon. 



1 74 Sun, Moon, and Stars. 

She is so little, and gravitation on her surface must 
be so feeble, that she might have failed to hold 
in the restless atmosphere which, perhaps, once 
clothed her. 

For the moon is very much smaller than the 
earth. Her diameter is about two-sevenths of the 
earths diameter ; her entire surface is about two- 
twenty-sevenths of the earth's surface ; her size is 
about two-ninety -ninths of the earth's size ; and 
her whole weight is about one-eightieth of the 
earth's weight. 

Attraction or gravitation on the surface of the 
moon is very different from what it is on the earth. 
Her much smaller bulk greatly lessens her power 
of attraction. While a man from earth would on 
the surface of the sun— supposing he could exist 
there at all — lie helpless, motionless, and crushed 
by his own weight, he would on the moon find 
himself astonishingly light and active. A leap 
over a tall house would be nothing to him. 

The moon, unlike the sun, has no light or heat 

of her own to give out. She shines merely by 

reflected light. Rays of sunlight falling upon her 

rebound thence and find their way earthward. 

- This giving of reflected light is not a matter 



More About the Moon. 175 

all on one side. We yield to the moon a great 
deal more than she yields to 11s. Full earth, seen 
from the moon, covers a space thirteen times as 
large as full moon seen from earth. 

Perhaps you may have noticed soon after new- 
moon, when a delicate crescent of silver light 
shows in the sky, that within the said crescent 
seems to lie the body of a round dark moon, only 
not perfectly dark. It shows a faint glimmer. 

That glimmer is called earth-shine. The bright 
crescent shines with reflected sunlight. The dim 
portion shines with reflected earth-light. 

What a journey those rays have had ! First 
leaving the sun, flashing through ninety-two mil- 
lions of miles to earth, rebounding from earth and 
flashing over two hundred and forty thousand 
miles to the dark shaded part of the moon, then 
once more rebounding and coming back, much 
wasted and enfeebled, across the same two hun- 
dred and forty thousand miles, to shine dimly in 
your eyes and mine. 

Now about the phases of the moon, that is, her 
changes from " new " to " full " and back again to 
" new." 

If the moon were a star-like body, shining by 



176 Sun, Moon, and Stars. 

her own light, she would always appear to be 
round. But as she shines by reflected sunlight, 
and as part of her bright side is often turned away 
from us, the size and shape of the bright part 
seem to vary. 

For, of course, only that half of the moon which 
is turned directly towards the sun is bright. The 
other half turned away is dark, and can give out 
no light at all, unless it has a little earth-shine to 
reflect. 

As the moon travels round the earth she 
changes gradually from new to full moon and 
then back to new again. 

" New moon " is when the moon in her orbit 
comes between the sun and the earth. The half 
of her upon which the sun shines is turned away 
from us and only her dark side is towards us. So 
at new moon she is quite invisible. It is at new 
moon that an eclipse of the sun takes place, when- 
ever the moon's orbit carries her in a line precisely 
between sun and earth. 

Passing onwards round the earth, the moon, as 
we get a little glimpse of her shining side, first 
shows a slender sickle of light, which widens more 
and more till she reaches her first quarter. She 
is then neither between earth and sun nor out- 



More About the Moon. 177 

side the earth away from the sun, but just at one 
side of us, passing over the earth's own orbit. 
Still, as before, half her body is lighted up by the 
sun. By this time half the bright part and half 
the dark part are turned towards us ; so that, see- 
ing the bright quarter, we name it the " first quar- 
ter." 

On and on round us moves the moon, showing 
more light at every step. Now she passes quite 
outside the earth's orbit, away from the sun. Not 
the slightest chance here of an eclipse of the sun, 
though an eclipse of the moon herself is quite pos- 
sible. But more of that presently. As she reaches 
a point in a line with earth and sun — only general- 
ly a little higher or lowSr than the plane of the 
earth's orbit — her round bright face, shining in the 
sun's rays, is turned exactly towards us. Then we 
have "full moon." 

Still she goes on. Once more her light narrows 
and wanes, as part of her bright half turns away. 
Again, at the "last quarter" as at the first, she 
occupies a " sideways " position, turning towards 
us half her bright side and half her dark side. 
Then she journeys on with lessening rim of light 
till she vanishes, and once more we have the dark 
invisible " new moon." 

Sim, Moon, etc. I 2 



1 78 Sun, Moon, and Stars. 

You may easily picture this for yourself. Let 
a candle be upon a table in a room otherwise dark. 
Stand near the table with a ball in your hand, 
which you must hold out at arm's length. Turn 
slowly round upon your feet, keeping your arm 
and hand motionless, and let the ball thus travel 
round you. 

Your own motion here is a matter of no import- 
ance. It is needful merely that you may keep your 
face towards the ball, and also that the position 
and slope of the ball may not vary. 

Begin by stretching out your arm straight to- 
wards the candle. Now the light is shining full 
upon the ball, lighting up one half of it. But of 
the bright half you see nothing. The dark side 
only is turned towards you. That is " new moon." 
If you put the ball exactly between your eyes and 
the candle it eclipses or hides the candle-flame, but 
by holding it an inch or two higher or lower you 
avoid an eclipse. 

Now move your arm slowly round to the left, 
moving yourself round with it so as to watch the 
ball intently. A rim of light will begin to show, 
gradually increasing, till of the half-ball which you 
can see, one quarter is light and one quarter is 
dark. In the case of the real moon the light quar- 



More About the Moon. 179 

ter only is visible and the dark is hidden, though 
in your ball you will see both. This is the " first 
quarter." 

Go on turning slowly round, watching the light 
space gradually widen. Now your arm is extended 
in a direction away from the candle. If the ball is 
in an exact line with the candle and your head, 
you will produce an " eclipse of the moon " by 
allowing your shadow to fall upon it. But by 
raising it a little higher you avoid this eclipse also. 
The candle-light still, as always, falls upon the ball, 
lighting up one half ; and now the whole of that 
half is turned towards you and the whole of the 
dark side is turned away. This is " full moon." 

Move onward again, spinning very slowly round 
with extended arm, and you will have diminishing 
light once more, till the ball passes through " last 
quarter " and again becomes new moon. 

An eclipse of the sun has been already de- 
scribed. An eclipse of the moon is an equally 
simple matter. 

An eclipse of the sun is caused by the dark 
solid body of the moon passing just between earth 
and sun, hiding the sun from us and casting its 
shadow upon the earth. 



1 80 Sun, Moon, and Stars. 

An eclipse of the moon is also caused by a 
shadow — the shadow of our own earth — falling 
upon the moon. 

Here again, if the plane of the moon's orbit 
were the same as ours, eclipses of the moon would 
be very common. As it is her orbit carries her 
often just a little too high or too low to be eclipsed ; 
and it is only now and then, at regular intervals, 
that she passes through the shadow of the earth. 

If a large solid ball is hung up in the air, with 
bright sunlight shining on it, the sunlight will cast 
a cone of shadow behind the ball. It will throw in 
a direction just away from the sun a long round 
shadow the same size as the ball at first, but taper- 
ing gradually off to a point. If the ball is near 
the ground, a round shadow will rest there almost 
as large as the ball. The higher the ball is 
placed, the smaller will be the round shadow, till 
at length, if the ball be taken far enough upwards, 
the shadow will not reach the ground at all. 

Our earth and all the planets cast just such 
tapering cones of dark shadow behind them into 
space. The cone always lies in a direction ex- 
actly away from the sun. 

It is when the moon comes into this shadow 
that an " eclipse of the moon " takes place. Some- 



More About the Moon. 181 

times she only dips half-way into it or just grazes 
along the edge of it, and that is called a " par- 
tial eclipse." Sometimes she goes in altogether, 
straight through the midst of the shadow, so that 
the whole of- her bright face for a short time 
grows quite dark. Then we have a " total lunar 
eclipse." 



1 82 Sun, Moon, and Stars. 



CHAPTER V. 

YET MORE ABOUT THE MOON. 

" Our God is in the heavens ; He hath done whatsoever He 
hath pleased." Psa. 115:3. 

There are two ways of thinking about the 
moon. One way is to consider her as merely the 
earth's attendant satellite. The other way is to 
consider her as our sister-planet, travelling with 
us round the central sun. 

The first is the more common view ; but the 
second is just as true as the first. 

For the sun does actually pull the moon to- 
wards himself with a very much stronger pulling 
than that of the earth. The attraction of the sun 
for the moon is more than double the attraction 
of the earth for the moon. If it were not that he 
pulls the earth quite as hard as he pulls the moon, 
he would soon overpower the earth's attraction 
and drag the moon away from us altogether. 

People are often puzzled about the orbit or 
pathway of the moon through the heavens. For 
in one sense they have to think of her as travel- 



Yet More About the Moon. 183 

ling round and round in a fixed orbit, with the 
earth in the centre. In another sense they have 
to think of her as always journeying onward 
with the earth in her journey round the sun, and 
thus never returning to the same point. 

There are two ways of meeting this difficulty. 

First of all, remember that the one movement 
does not interfere with the other. Just as in the 
case of the earth travelling round the sun and also 
travelling onward with him through space, just as 
in the case of a boy walking round and round a 
mast and also being borne onward by the mov- 
ing vessel, so it is here. The two movements are 
quite separate and independent of each other. 

As regards the earth alone, the moon journeys 
round and round perpetually, not in a circle, but 
in a pathway which comes near being an ellipse. 

As regards the actual line which the moon's 
movements may be supposed to draw in space, it 
has nothing elliptical about it, since no one point 
of it is ever reached a second time by the moon. 

But according to this last view of the question, 
nobody ever can or will walk in a circle or an 
oval. Take a walk round your grass-plot, measur- 
ing your distance carefully at all points from the 
centre. Is that a circle? All the while you moved 



1 84 Sun, Moon, and Stars. 

the surface of the earth was rushing along and 
bearing you with it, and the whole earth was 
hurrying round the sun, and was being also car- 
ried by him in a third direction. Whatever point 
in space you occupied when you started, you can 
never fill that particular part of space ag am. The two 
ends of your so-called circle can never be joined. 

But then you may come back to the same point 
on the grass as that from which you started. And 
this is all that really signifies. Practically you 
have walked in a circle. Though not a circle as 
regards space generally, it is a circle as regards 
the earth. 

So also the moon comes back to the same point 
in her orbit round the earth. Letting alone the 
question of space, and considering only the* earth, 
the moon has — roughly speaking — journeyed in 
an ellipse. 

You may, however, look at this matter in quite 
another light. 

Forget about the moon being the earth's satel- 
lite, and think of earth and moon as two sister- 
planets going round the sun in company. 

The earth, it is true, attracts the moon. So also 
the moon attracts the earth, though the far greater 
weight of the earth makes her attraction to be 



Yet More About the Moon. 185 

far greater. If earth and moon were of the same 
size they would pull each other with equal force. 

But though the pull of the earth upon the 
moon is strong, the pull of the sun upon the moon 
is more than twice as strong. And greatly as the 
earth influences the moon, yet the actual centre of 
the moon's orbit is the sun and not the earth. 
Just as the earth travels round the sun, so also 
the moon travels round the sun. 

The earth travels steadily in her path, being 
only a little swayed and disturbed by the attrac- 
tion of the moon. The moon, on the contrary, 
while travelling in her orbit is very much swayed 
and disturbed indeed by the earth's attraction. 
In fact, instead of being able to journey straight 
onwards like the earth, her orbit is made up of 
a succession of delicate curves or scallops passing 
alternately backwards and forwards over the orbit 
of the earth. Now she is behind the earth, now in 
front of the earth ; now between earth and sun, 
now outside the earth away from the sun. The 
order of positions is not as here given, but each 
is occupied by her in turn. Sometimes she moves 
quickly, sometimes she moves slowly, just accord- 
ing to whether the earth is pulling her on or 
holding her back. 



1 86 Sun, Moon, and Stars. 

Two hundred and forty thousand miles sounds 
a good deal. That is the medium distance of 
earth from moon. But it is, after all, a mere 
nothing compared with the ninety-two or ninety- 
three millions of miles which separate the sun 
from the earth and moon. 

If we made a small model, with the sun in the 
centre and the earth and moon travelling a few 
inches off, only one slender piece of wire would be 
needed to represent the path of earth and moon 
together. For not only would the earth and the 
moon be so small as to be quite invisible, but the 
whole of the moon's orbit would have disappeared 
into the thickness of the single wire. 

This question of the moon's motions is in its 
nature intricate and in its details quite beyond 
the grasp of any beginner in astronomy. 

But so much at least may be understood, that 
though the earth's attraction powerfully affects 
the moon, and causes in her motions perturbations 
such as have been already spoken about as taking 
place among the planets, yet in reality the great 
controlling power over the moon is the attraction 
of the sun. 

The tides of the ocean are chiefly brought 
about by the moon's attraction. The sun has 



Yet More About the Moon. 187 

something to do with the matter, but the moon is 
the chief agent. 

This action of the moon is best seen in the 
southern hemisphere, where there is less land. As 
the moon travels slowly round the earth her at- 
traction draws up the yielding waters of the ocean 
in a vast wave, which travels slowly along with 
her. The same pulling which thus lifts a wave 
on the side of the earth towards the moon also 
pulls the earth gently away from the water on 
the opposite side, and causes a second wave there. 
The parts of the ocean between these two huge 
waves are depressed, or lower in level. 

These two waves on opposite sides of the earth 
sweep steadily onward, following the moon's move- 
ments — not real but seeming movements, caused 
by the turning of the earth upon her axis. 

Once in every twenty-four hours these wide 
waves sweep round the whole earth in the southern 
ocean. They cannot do the same in the north, 
on account of the large continents, but offshoots 
from the south waves travel northward, bringing 
high tide into every sea and ocean inlet. 

If there were only one wave, there would be 
only one tide in each twenty -four hours. As 
there are two waves, there are two tides, one 



1 88 Sun, Moon, and Stars. 

twelve hours after the other. In the space be- 
tween these two high tides we have low tide. * 

Twice every month we have the greatest rise 
and fall of the tides. These are called " spring 
tides." Twice every month we have the least 
rise and fall. These are called "neap tides/' 

When the moon is between us and the sun, 
or when she is "new moon/' there are spring 
tides ; for the pull or attraction of sun and moon 
upon the ocean act exactly together. It is the 
same at full moon, when once more the moon is 
in a straight line with earth and sun. 

But at the first and last quarters, when the 
moon has her sideways position, and when the 
sun pulls in one direction and the moon pulls in 
another, each undoes a little of the other's work. 
Then we only have neap tides, for the wave 
raised is smaller and the water does not flow so 
high upon our shores. 

In speaking of the surface of the moon we are 
able only to speak about one side. The other is 
entirely hidden from us. This is caused by the 
curious fact that the moon turns on her axis and 
travels round the earth in exactly the same 
length of time. 



Yet More About the Moon. 189 

One half of the moon is thus always turned 
towards us, though of that half we can only see 
so much as is receiving the light of the sun. But 
the half turned in our direction is always the 
same half. 

One part of the moon — not quite so much as 
half, though always the same portion — is turned 
away from us. A small border on each side of 
that part becomes now and then visible to us, 
owing to certain movements of the earth and 
the moon. 

What sort of a landscape may lie in the un- 
known district it is idle to imagine. Many 
guesses have been made. Some have supposed it 
possible that air might be found there, that water 
might exist there, that something like earthly 
animals might live there. 

These, however, are now notions of the past, 
no longer to be entertained. Judging from mere 
earthly experience, nothing seems more unlikely 
than that air and water should be banished from 
one half of a world and collected together in the 
space remaining. Moreover, as already explained, 
we know how extremely natural a thing it is that 
the moon should have lost her atmosphere 
through the weakness of her attractive power; 



1 90 Sun, Moon, and Stars. 

and this would affect equally all sides of the 
globe. If any air at all exists there, it must be 
in density less than the two-thousandth part of 
what we breathe. 

It seems almost equally clear that water must 
be entirely absent. No signs of water-action are 
visible in the craggy mountains and deep 
craters. 

If there at all, it could only be in the form of 
ice, since the absence of an atmosphere keeps the 
surface of the moon, even during the glare of its 
long day, below zero. 

The craters which honeycomb the surface of 
the moon are various in size. Many of the larger 
ones are from fifty to a hundred miles in diam- 
eter. These huge craters, or, as we may call 
them, deep circular plains, are surrounded by 
mighty mountain ramparts rising to the height 
of thousands of feet. Usually they have in their 
centre a sugar - loaf or cone-shaped mountain, or 
even two or more such mountains, somewhat 
lower in height than the surrounding range. 

The sunset-lights upon certain of these distant 
mountain-peaks were first watched by Galileo 
through his telescope, and have since been seen 



Yet More About the Moon. 191 

by many an observer— intense brightness con- 
trasting with intense blackness of shadow. 

In addition to her great craters the moon 
seems to be thickly covered with little ones, 
many being as small as can be seen at all through 
a telescope. 

Whether these are all volcano-craters remains 
to be discovered. It is not supposed that any of 
them are now active. From time to time signs 
of faint changes on the moon's surface have been 
noticed, which it was thought might be owing to 
volcanic outbursts. Such an outburst as the 
worst eruptions of Mt. Vesuvius would be invisi- 
ble at this distance. But the said changes may 
be quite as well accounted for by the startling 
fortnightly variations of climate which the moon 
has to endure. The general belief now inclines 
to the idea that the moon-volcanoes are extinct, 
though no doubt there was in the past great vol- 
canic activity there. 

A description has been given earlier of the 
rain of meteorites constantly falling to our earth, 
and only prevented by the atmosphere from 
becoming serious. 

The moon has no such protecting atmosphere, 
and the amount of cannonading which she has 



192 Sun, Moon, and Stars. 

to endure must be by no means small. Perhaps 
in past times, when her slowly-cooling crust was 
yet soft, these celestial missiles . showering upon 
her may have occasionally made deep round 
holes in her surface. 

This is another guess, which time may prove 
to be true. Guesses at possible explanations of 
mysteries do no harm so long as we do not accept 
them for truth without ample reason. 

Beside the craters and their surrounding bar- 
riers there are ranges of mountains on the moon, 
and flat plains which were once named "seas" 
before it was found that water did not exist there. 
Astronomers also see bright ridges, or lines, or 
cracks of light, hard to explain. 

One of the chief craters is called " Ptolemy," 
and in size it is roughly calculated to be no less 
than one hundred and fourteen miles across. 
Another, "Copernicus," is about fifty -six miles, 
and another, "Tycho," about fifty -four miles. 
The central cone-mountain of Tycho is five thou- 
sand feet high. The crater of " Schickard " is 
supposed to be as much as one hundred and 
thirty-three miles in diameter. 

The so-called " seas " are those large dark 
spots to be seen on the moon's surface in the 



Yet More About the Moon. 193 

shape of " eyes, nose, and mouth/' or of the 
famous old man with his bundle of sticks. The 
brighter parts are the more mountainous parts. 

The chief ranges of lunar mountains have 
been named by astronomers after mountains on 
earth, such as the Apennines, the Alps, the Cau- 
casian range, the Carpathian, and the Altai 
Mountains. 

Note. — With reference to the question of tides, slightly 
touched upon in this chapter, a few words of additional explana- 
tion have been kindly sent to me by a naval officer, so clear and 
concise that I insert them as they stand : 

" When the tidal wave is advancing it causes a current to run 
in the direction of its advance. This current is called the 
'flood tide.' 

" When the highest part of the tidal wave has reached any 
place it is said to be ' high water ' at that place. 

" Very soon after high water the receding of the tidal wave 
causes the current to run in the opposite direction to the flood, 
and to continue running till the lowest point of the tidal w T ave 
has been reached. This receding current is called the " ebb 
tide," and its lowest point is called ' low water.' 

" Both at high and low water there is a brief period when 
the tide neither ebbs nor flows. This period is called ' slack 
water.' " 



Sun, Moon, etc. 



13 



1 94 Sun, Moon, and Stars. 



CHAPTER VI. 

MERCURY, VENUS, AND MARS. 

" Thou hast made the heaven and the earth by Thy great 
power and stretched-out arm, and there is nothing too hard for 
Thee."— Jer. 32:17. 

Once again we have to journey through the 
high-roads of the Solar System, paying a brief 
visit to each in turn of our seven chief brother- 
and-sister planets and learning a few more leading 
facts about them. Having gone the same way 
before, it will not now seem quite so far. 

Busy hurrying Mercury ! we must meet him 
first in his wild rush through space. If he were 
to slacken speed for a single instant, he would 
begin to fall with fearful rapidity towards the sun. 
And if Mercury were to drop into one of those 
huge black chasms of rent furnace-flame on the 
sun's surface, there would be a speedy end to his 
life as a planet. 

Mercury's year is about one quarter the length 
of our year : and his day is believed by Schiapa- 
relli, from certain observations made, to be iden- 
tical in length with the planet's year. This, how- 



Mercury, Venus, and Mars. 195 

ever, is as yet by no means certain. If true, it 
would mean that Mercury revolves round the sun, 
presenting to him always one side only, and never 
the other, just as our moon revolves round the 
earth. 

Whether Mercury's axis slopes like earth's 
axis we do not yet know. More can be said about 
his orbit. The earth's orbit, as before explained, 
is not a circle, but an ellipse or oval. Mercury's 
orbit is an ellipse also, and a much longer — or, as 
it is called, a more eccentric — ellipse. The earth 
is three millions of miles nearer to the sun at one 
time of the year than six months before or after. 
Mercury is no less than fifteen millions of miles 
nearer at one time than another, which must make 
a marked difference in the amount of heat re- 
ceived. 

Even when the distance is greatest, the sun as 
seen from Mercury looks more than four times as 
large as the sun we see. 

What a blazing splendor of light ! It is not 
easy to imagine human beings living there in such 
heat and glare, and with either no changes of sea- 
son at all or such very short seasons rapidly fol- 
lowing one another. Mercury may, not impossi- 
bly, abound with living creatures of some sort ; 



196 Sun, Moon, and Stars. 

but they would have to be an altogether different 
kind of creatures from any seen on earth. True, 
a very considerable power of adaptation is found 
here in many animals, especially in man ; so that 
great varieties of climate, from extreme heat to 
extreme cold, can be endured. It is not easy to 
say how far such power of adaptation to circum- 
stances may reach. Still, the extremest heat 
ever felt on earth is as nothing beside that of "Mer- 
cury ; and the common-sense view of things is 
very much opposed to the {fossibility of any life 
on Mercury identical in kind with any life known 
on earth. 

The suggestion has been made that a moist 
dense atmosphere might possibly help to ward off 
the overpowering heat and to make the planet 
more habitable. Experience, however, argues 
against this theory. Our earthly atmosphere acts 
in a precisely contrary fashion, serving as a store- 
house for heat, and rendering our planet much 
warmer than if no air existed. 

There is, after all, no need to conclude hastily 
that all these worlds in our neighborhood are, or 
must be, inhabited at this present time. Why, 
indeed, should they? With perfect ease each 
world could have been adapted by divine power 



Mercury, Venus ^ and Mars, 197 

to its inhabitants, or the inhabitants to each world. 
But, quite conceivably, they may be destined for 
some entirely different purpose, lying outside the 
range of our knowledge and imagination. Or 
they may be still in process of preparation for 
future inhabitants, as, during countless ages, our 
earth was in preparation for the little span of 
man's life upon her surface. We need not thrust 
our earthly notions of haste into the thought of 
the vast cycles of a universe formed in the infi- 
nite leisure of the divine counsels. 

If, in addition to a possible atmosphere, Mer- 
cury were surrounded habitually, as some have 
conjectured, by an envelope of heavy clouds, this ? 
might no doubt, to some extent, modify the des- 
perate heat. 

The small size of Mercury makes attraction on 
his surface much less than on earth. A lump of 
iron weighing 011 earth one pound would weigh 
on Mercury only about seven ounces, or less than 
half as much. So a man would be a very light 
leaper indeed there, and an elephant might be 
quite a frolicsome animal. 

If there should be star-gazers in Mercury, the 
earth and Venus must both be beautiful to look 
upon. Each of the two would shine far more 



198 Sun, Moon, and Stars, 

brightly than Jupiter as seen at his best from 
earth. 



Like Mercury, Venus, the next planet, has an 
orbit lying inside our orbit. Mercury and Venus 
are always nearer to the sun than we are. 

And if Mercury and Venus travelled round the 
sun in orbits the planes of which were exactly the 
same as the plane of the earth's orbit, we should 
very often see them creeping over the surface of 
the sun. 

Not that they really " creep over " it ; only, as 
they journey between the sun and us, we can see 
' them pass like little black dots across the sun's 
disc. This is the same thing as when the moon 
passes across the sun's disc and eclipses it. But 
Mercury and Venus are too far away from us to 
cause any eclipse of the sun's light. 

These crossings of the sun's face, or " transits," 
as they are called, have been important matters. 
The transit of Venus especially was once eagerly 
looked for by astronomers, since by close observa- 
tions of Venus' movements and positions the dis- 
tance of the sun could at that time be better calcu- 
lated than in any other way. Other methods are 
now coming into vogue. 



Mercury, Venus, and Mars. 1 99 

The transits of Venus are rare. Two come 
near together, separated by only eight years, and 
then for more than one hundred years the little 
dark body of Venus is never seen from earth to 
glide over the sun's photosphere. There was a 
transit of Venus in the year 1761 and another in 
the year 1 769. There was a transit of Venus in 
1874, and there was also another in 1882. At the 
last transit it was found that the sun was only 
about ninety-one or ninety-two millions of miles 
away, while later calculations of a different kind 
have fixed the amount as close upon ninety-three 
millions. 

The reason why these transits happen so sel- 
dom is that the orbits of Mercury and Venus lie in 
rather a different plane or level from the earth's 
orbit. So, like the moon, though often passing 
between us and the sun, they generally go just a 
little higher or just a little lower than his bright 
face. 

Mercury and Venus show phases like the moon, 
although they do not circle round the earth as the 
moon does. These " phases," or changes of shape, 
are probably never visible except through a tele- 
scope. 

It will be easier to think about the phases of 



200 Sun, Moon, and Stars. 

Venus alone than to consider both together. Her 
orbit lies within the earth's orbit, and the earth 
and Venus travel round the sun — as do all the 
planets — in the same direction. But as Venus' 
pathway is shorter than ours, and as her speed is 
greater, she is much the quicker about her yearly 
journey, and she overtakes us again and again at 
different points of our orbit in turn. 

At one time she comes between us and the 
sun. That is her nearest position to us, and she 
is then only about twenty-five millions of miles 
distant. A beautiful sight she would be, but 
unfortunately her bright side is entirely turned 
away and only her dark side is turned towards 
us. So then she is " new Venus," and is invisible. 

At another time she is completely beyond the 
sun and at her farthest position away from us. 
Her shining is quite lost in the sun's rays coming 
between. And though we get a good view of 
her as " full Venus " at a little to one side or the 
other, yet so great is her distance — as much as one 
hundred and fifty-seven millions of miles — that 
her size and brightness are very much lessened. 

Between these two nearest and farthest points 
she occupies two middle distances, one on each 
side of the sun. Then, like the moon at her 



Mercury, Venus, and Mars. 201 

" quarters/' she turns to us only half of her bright 
side. But this is the best view of Venus that we 
have, as a brilliant unt winkling star-like form — 
the Evening Star of ancients and of poets. 

Between these four leading positions Venus is 
always travelling gradually from one to another — 
always either waxing or waning in size and in 
brightness. 

Mercury passes through the same seeming 
changes. 

If Venus owned inhabitants they would have 
a glorious view of the earth with her moon. At 
the time when the two planets are nearest to- 
gether, and when she is only "new Venus" to 
us, a dark and invisible body, the earth is " full 
earth" to Venus. The very best sight we ever 
have of Venus cannot come near that sight. But 
if Venus should be so often covered with heavy 
clouds as some have thought possible, this must 
greatly interfere with any habits of star-gazing. 

Venus and the earth have often been called 
twin-sister planets. There are many points of 
likeness between them. In size at least they 
differ little. Venus, as well as Mercury, is be- 
lieved by Schiaparelli to have a day equal in 



202 Sun, Moon, and Stars. 

length to the planet's year, one face only of 
the planet being thus turned always downward. 
M. Trouvelot, on the contrary, as a result of 
other observations, reverts to the old idea that 
Venus has a day like in length to that of her 
twin-sister, Earth — about twenty-four hours long. 
It is impossible as yet to know which will prove 
to be in the right. 

M. Trouvelot also believes that certain bright 
spots occasionally seen on Venus are very lofty 
mountains showing their peaks above the thick 
atmosphere. This again is a reversion to, or at 
least an additional proof of, an idea many years 
old, that mountains on Venus tower to three or 
four times the height of our stateliest earthly 
summits. 

There is a good deal of uncertainty about the 
climate of Venus. The heat there must greatly 
surpass heat ever felt on earth — the sun be- 
ing about double the apparent size of our sun 
and pouring out nearly double the amount of 
light and heat that we receive in our tropics in 
the hottest day ever known. Human beings, 
accustomed to earthly heat, could scarcely exist 
or keep their eyesight under such a blaze and 
glare as this must imply. 



Mercury, Venus, and Mars. 203 

It it believed also that the axis of Venus, in- 
stead of being slanted only as much as the earth's 
axis, is tilted much more. Even if the tilting is 
less than some have supposed, it is probably very 
considerable. If Venus really does "lie over" in 
such a manner, certain startling changes of cli- 
mate, unpleasant changes according to our ideas, 
would take place. 

Like earth, Venus would have her two arctic 
regions, where a burning summer's day would 
succeed a bitter winter's night, each half a year 
in length. She would have also her tropical re- 
gion, only in that region intense cold would alter- 
nate with intense heat — brief seasons of each in 
turn. And between the tropics and the arctic 
regions would lie wide belts, by turns entirely 
tropical and entirely arctic. The rapidity and 
severity of these changes, following one another 
in a year about as long as eight of our months, 
would seem to be too much for any human 
frame to endure. 

But it all rests upon an if. And we may be 
quite sure that if there are any living creatures 
in Venus their frames are well suited to the cli- 
mate of their world. 



204 Sun, Moon, and Stars. 

Though Mars is one of the inner group of four 
small planets, divided by the zone of asteroids 
from the outer group of four great planets, yet 
he belongs to the outside set of Superior Planets. 
His orbit surrounds ours, being at all points far- 
ther off from the sun. 

Very slight " phases" have been seen in Mars. 
He turns to us from time to time just enough 
of his dark side to prove that he has a dark side 
and that he does not shine like a star by his own 
light. But the phases are by no means marked 
as with Venus. 

It was long believed that Mars possessed no 
moons. Two very small ones have, however, been 
lately found circling round him. They have been 
named Deimos and Phobos, after the "sons of 
Mars" in Greek mythology. Deimos travels round 
Mars in thirty-nine hours, while Phobos performs 
the same journey in the astonishingly short period 
of seven hours and a half ! 

Mars is not only much smaller than the earth, 
but a good deal less dense in his "make." His 
material is only about three-quarters as heavy as 
an equal amount of the earth's material. A very 
heavy man on earth would be a most light and 
active individual on Mars. Gold taken from earth 



Mercury, Venus, and Mars. 205 

to Mars would weigh there no more than tin 
weighs upon earth. 

There are good reasons for believing that 
Mars has an atmosphere. Indeed it has been 
conjectured that Mars may possibly be some- 
where about one of the smallest-sized worlds able 
permanently to retain their atmospheres by force 
of gravitation. 

The surface of Mars has been more studied, 
because it can be more studied, than that of any 
other planet in our system. It is well placed for 
observation, being outside the earth instead of 
between us and the sun, and it is also compara- 
tively near. True, at his very nearest, Mars does 
not draw closer than thirty-five millions of miles, 
and one has to be very cautious in making state- 
ments about a world thirty-five millions of miles 
away. But this is not much compared with the 
distance of Jupiter. 

And the surface of Mars presents features 
well worthy of study, albeit perplexing. Here 
and there, it is true, cloud-forms seem to sweep 
over the landscape, blotting out what lies below. 
Still, though such appearances come and go, they 
do go as well as come ! Mars is not, like Jupiter 
and Saturn, permanently wrapped in such masses 



2o6 Sun, Moon, and Stars. 

of vapor that one cannot tell whether any solid 
body at all lies within. 

The reddish color of Mars is well known. 
This does not vanish in the telescope, but it is 
found that parts only have the reddish hue, while 
other parts are dark and greenish. These mark- 
ings have been so closely examined that more is 
known about the geography of Mars than of any 
other world outside of our own. It is supposed 
that they may be continents and oceans, and 
names have been given to them, such as Dawes 
Continent, Herschel Continent, Airy Sea, Hug- 
gins' Inlet, and so on. 

Land and water — if these markings really are 
such— seem to be very differently distributed on 
Mars from what they are on earth. Here we 
have about three times as much water as land, 
and to get from one continent to another without 
crossing the sea is in some cases impossible. 

But a traveller there might go most conve- 
niently to and fro, hither and thither, to all parts 
of his world, either on land or on water, without 
any change. If he preferred water, he would 
never need to set foot on land, and if he preferred 
land, he would never need to enter a boat. The 
two are so curiously mingled together, narrow 



Mercury, Venus, and Mars. 207 

necks of land running side by side with long, 
narrow sea-inlets, that Atlantic and Pacific Oceans 
are unknown. 

These landscape features of the planets seem 
to be not absolutely changeless, like the conti- 
nents and oceans of earth, and of course any alter- 
ations seen by us from earth, in the course of a 
few years, must imply vast changes of outline 
there. It may be that Mars is now in a state 
which earth passed through many ages ago, a 
state of rapid geological change, rising and sink- 
ing of continents and shifting of oceans. But it 
is at least quite as probable that the changes are 
in the main atmospheric, and that the continents 
and canals really alter very little. 

If clouds do actually float in the atmosphere 
of Mars, this means the existence of water in 
Mars. Doubtless rain sometimes falls there. 

Two singular white spots are to be seen at the 
north and south poles which are most probably 
polar ice and snow. Anybody looking at our 
earth in like manner from a distance, might per- 
ceive two such white snow-caps. These caps are 
seen to vary with the seasons. When the north 
pole of Mars is turned towards the sun the white 
spot there grows smaller ; and at the same time, 



2o8 Sun> Moon, and Stars, 

the south pole of Mars being turned away from 
the sun, the white spot there grows larger. 
Again, when the south pole is towards the sun, 
and the north pole away from the sun, the white 
spot at the south is seen to be the smallest and 
the white spot at the north is seen to be the 
largest. This is exactly what takes place in the 
summers and winters of our north and south 
poles. 

It is rather curious that Mars' caps should be 
much smaller than ours, since Mars is farther 
from the sun. But Mars is thought to contain 
proportionately less water than our earth does; 
and a drier atmosphere would at once account 
for a lessened amount of snow. 



Jupiter. 209 



CHAPTER VII. 

JUPITER. 

" Whatsoever the Lord pleased, that did He in heaven and in 
earth." — Psa. 135:6. 

Passing at one leap over the belt of tiny aste- 
roids, about which we know little beyond their 
general movements and the size and weight of a 
few among them, we reach at once the giant plan- 
et Jupiter — mighty Jupiter, hurrying ever onward 
with a speed not indeed equal to that of Mercury 
or of our earth, yet eighty times as rapid as the 
speed of a cannon-ball ! 

Think of a huge body, equal in bulk to twelve 
hundred earths and in weight to over three hun- 
dred earths, rushing ceaselessly through space at 
the rate of seven hundred thousand miles a day ! 

Jupiter's shape is greatly flattened at the poles. 
He spins rapidly on his axis once in nearly ten 
hours, and has therefore a five hours' day and a 
five hours' night. As the slope of his axis is ex- 
ceedingly slight, he can boast little or no changes 
of season. The climate near the poles has never 
much of the sun's heat. In fact all the year round 

Sun, Moon, etc. 1 4 



2io Sun, Moon, and Stars. 



the sun must shine upon Jupiter much as he 
shines on the earth at the equinoxes. 

But the amount of light and heat received by 
Jupiter from the sun is only about one twenty-fifth 
part of that which we receive on earth ; and the 
sun as seen from Jupiter can have but a small 
round surface not even one-quarter the diameter 
of the sun we see in the sky. 

When looked at with magnifying power the 
bright star-like Jupiter grows into a broad,' softly- 
shining disc or. plate, with flattened top and bot- 
tom, and four tiny bright moons close at hand. 
Sometimes one moon is on one side and three are 
on the other ; sometimes two are on one side and 
two on the other; sometimes one or more are 
either hidden behind Jupiter or passing in front 
of him. Jupiter has also curious markings on 
his surface, visible through a telescope. These 
markings often undergo changes, for Jupiter is no 
chill, fixed, dead world such as the moon seems 
to be. 

There are dark belts and bright belts, usually 
running in a line with the equator, from east to 
west. Across the regions of the equator lies com- 
monly a band of pearly white, with a dark band on 
either side of " coppery, ruddy, or even purplish " 



Jupiter. 2 1 1 

hue. Light and dark belts follow one after another 
up to the north pole and down to the south pole. 

When we talk of " north and south poles" in 
the other planets, we merely mean those poles 
which point towards those portions of the starry 
heavens which we have chosen to call " northern " 
and " southern." 

You know that all the chief planets travel round 
the sun in very nearly the same plane or flat sur- 
face that we do ourselves. That plane is called the 
" plane of the ecliptic." 

Suppose that you had an enormous sheet of 
cardboard, and that in the middle of this cardboard 
the sun were fixed, half his body being above and 
half below. At a little distance, fixed in like man- 
ner in the card, would be the small body of the 
earth, half above and half below, her axis being in 
a slanting position. 

The piece of cardboard represents what is 
called in the heavens the plane of the ecliptic — an 
imaginary flat surface cutting exactly through the 
middle of the sun and of the earth. 

If the planets all travelled in the same precise 
plane, they would all be fixed in the cardboard 
just like the earth, half the body of each above and 



2 1 2 Sun, Moon, and Stars. 

half below. As they do not so travel, some would 
have to be placed a little higher, some a little lower, 
according to what part of their orbits they were on. 

This supposed cardboard "plane of the eclip- 
tic " would divide the heavens into two halves. 
One half, containing the constellations of the Great 
Bear, the Little Bear, Cepheus, Draco, and others, 
would be called the Northern Heavens. One end 
of the earth's axis, pointing just now nearly to the 
Polar Star, we name the North Pole ; and all poles 
of planets pointing towards this northern half of 
the heavens are in like manner named by us their 
north poles. 

With regard to west and east, lay in imagina- 
tion upon this cardboard plane a watch, with its 
face upward, remembering that all the planets and 
nearly all the moons of the Solar System are said 
both to spin on their axes and to travel in their 
orbits round the sun from west to east. Note how 
the hands of your watch would move in such a 
position. The "west to east " motions of planets 
and moons would be in exactly the opposite direc- 
tion from the motions of the watch-hands. 

To return to Jupiter. It is believed that these 
bands of color are owing to a heavy dense atmo- 
sphere loaded with vast masses of cloudy vapor. 



Jupiter. 213 

By the " size " of Jupiter we really mean the size 
of this outside envelope of clouds. How large the 
solid body within may be, or whether there is any 
such solid body at all, we do not know. The ex- 
treme lightness of Jupiter as compared with his 
great size has caused strong doubts on this head. 

The white belts are supposed to be the outer 
side of cloud-masses shining in the sunlight. Tra- 
vellers in the Alps have seen such cloud-masses 
spreading over the whole country beneath their 
feet, white as driven snow, and shining in the sun- 
beams which they were hiding from villages below, 
or looking like masses of cotton-wool, from which 
the mountain-peaks rose sharply here and there. 

The dark spaces between seem to be rifts or 
breaks in the clouds. Whether, when we look at 
those dark spaces, we are looking at the body of 
Jupiter, or only at lower layers of clouds, is not 
known. But sometimes blacker spots show upon 
the dark cloud-belts, and this seems rather as if 
they were only lower layers of clouds, the black 
spots giving us peeps down into still lower and 
deeper layers, or else perhaps to the planet itself. 

These appearances remind one strongly of the 
sun-spots, each with its penumbra, umbra, and 
nucleus. 



214 Sun, Moon, and Stars. 

Occasionally bright white spots show instead of 
dark ones. It is thought that they may be caused 
by a violent upward rush of dense clouds of 
white vapor. The white spots again recall the sun 
and his faculce. 

Jupiter's bands are not fixed. Great changes 
go on constantly among them. Sometimes a 
white band will turn dark-colored or a dark band 
will turn white. Sometimes few and sometimes 
many belts are to be seen. Sometimes a dark belt 
will lie slanting across the others, nearly from 
north to south. Once, in a single hour, an entire- 
ly new belt was seen to come into shape. Another 
time two whole belts vanished in one day. The 
bands in which such rapid movements are seen 
are often thousands of miles in breadth. 

Sometimes these wide zones of clouds will re- 
main for weeks the same. At another time a 
break or rift in them will be seen to journey swift- 
ly over the surface of the planet. 

The winds on earth are often destructive. A 
hurricane moving at the rate of ninety miles an 
hour will carry away whole buildings and level 
entire plantations. Such hurricanes rarely if ever 
last more than a few hours. 

But winds in Jupiter, judging from the move- 




- (X 



Jupiter. 215 

ments of the clouds, often travel at the rate of one 
hundred and fifty miles an hour, and that not for 
hours only, but for many weeks together. What 
manner of living beings could stand such weath- 
er may well be questioned. 

Another difficulty which arises is as to the cause 
of these portentous disturbances on Jupiter. Our 
earthly storms are brought about by the heat of 
the sun acting on our atmosphere. But the sun- 
heat which reaches Jupiter seems far from enough 
to raise such vast clouds of vapor and to bring 
about such prolonged and tremendous hurricanes. 

What if there is another cause ? What if Jupi- 
ter is not a cooled body like our earth, but a liquid 
seething, bubbling mass of fiery heat — just as we 
believe our earth was once upon a time, in long 
past ages, before her outside crust became cold 
enough for men and animals to live thereon? 

Then indeed we could understand how, instead 
of oceans lying on his surface, all the water of 
Jupiter would be driven aloft to hang in masses of 
steam or be condensed into vast cloud-layers. Then 
we could understand why a perpetual stir of rush- 
ing winds should disturb the planet's atmosphere. 

In that case would Jupiter be a planet at all ? 

Certainly — in the sense of obeying the sun's 



2i6 Sun, Moon, and Stars. 

control. Our earth was once, we believe, a globe 
of melted matter, glowing with heat, and, farther 
back still, possibly, a globe of gas. Some people 
are very positive about these past changes ; but it 
is wise not to be over-positive where we cannot 
know to a certainty what has taken place. How- 
ever, Jupiter may have cooled down only to the 
liquid state, and if he goes on cooling he may by- 
and-by gain a solid crust like the earth. Times of 
long and slow preparation are often needed alike 
by individuals, by nations, and by worlds. If Ju- 
piter is ever to be an inhabitable planet, that goal 
must lie still a long way ahead. 

A few words as to the moons ever circling 
round and round the body of Jupiter. 

Slight mention has been made earlier of a 
fifth moon, recently detected by Prof. Barnard 
in the Lick Observatory. The discovery has not 
yet been verified elsewhere. 

This new inner satellite appears to be very 
tiny, only perhaps one hundred miles or so in 
diameter, and it is seen in the telescope as a star 
of the thirteenth or fourteenth magnitude. It lies 
very near to Jupiter, at a distance from that 
planet's centre of less than 117,000 miles, and it is 
believed to spin round its huge primary in less 



Jupiter, 2 1 7 

than twelve earthly hours — a needful speed to 
counterbalance the force of gravitation drawing 
it towards Jupiter. 

Some years ago a thought was put forward as 
to Jupiter's moons. It was suggested that, while 
Jupiter himself must be regarded as obviously 
unfitted in his present condition to support living 
creatures, it might be that the little moons were 
inhabited, and that Jupiter served as a kind of 
secondary sun to his satellites. Closer observa- 
tion and growing knowledge have not tended to 
confirm this notion, and it must now be booked 
as thrown aside. 

The nearer moons have indeed a magnificent 
view of Jupiter as an enormous bright disc in 
their sky, shining radiantly with reflected sun- 
light ; and the varying tints and stormy changes 
in the cloud -belts, viewed from near at hand, 
must present marvellous effects. 

Just as Mercury, Venus, Earth, and Mars travel 
round the sun at different distances, nearly in the 
same plane, so do Jupiter's moons travel round 
him at different distances, nearly in the same 
plane. The four outer moons are always seen in 
a line, not one high and another low, one near his 
pole and another near his equator. 



2 1 8 Sun, Moo7t, and Stars. 

The nearest of the four to Jupiter, named Io, 
is said to be over two thousand miles in diameter, 
travels round Jupiter in lesfc than two of our days, 
and is eclipsed by Jupiter's shadow once in every 
forty-two hours. 

The next moon, Europa, is rather smaller, 
takes over three days to its journey, and suffers 
eclipse once in every eighty-five hours. 

The next moon, Ganymede, is believed to be 
considerably larger than Mercury, journeys round 
Jupiter once a week, and is eclipsed once every 
hundred and seventy-one hours. 

The outer moon, Callisto, is also said to be 
slightly larger than Mercury, performs its journey 
in something more than sixteen days, and from 
its greater distance suffers eclipse less often than 
the other three. 

The nearest of the four is more than two hun- 
dred thousand miles from Jupiter ; the farthest is 
more than one million miles off. 

The fact of these eclipses, and of the shadow 
cast by Jupiter's body, shows that though he may 
give out a great deal of heat, he cannot shine with 
intrinsic light, or it would prevent any shadow 
from being thrown by the sunlight. 



Saturn. 219 



CHAPTER VIII. 

SATURN. 

" He hath made everything beautiful in His time." — Eccles. 
3:11. 

The system of Jupiter is a simple system com- 
pared with that of Saturn, next in order. 

Jupiter has only four or five moons, while 
Saturn has eight, and in addition to these he has 
three wonderful rings. Neither rings nor moons 
can be seen without a telescope, on account of 
Saturn's great distance from us — more than three 
thousand times the distance of the moon, or up- 
wards of eight hundred and twenty millions of 
miles. 

Saturn does not equal his mighty brother 
Jupiter in size, though he comes near enough in 
this respect to be called often his "twin," just as 
that small pair of worlds, Venus and Earth, are 
called " twins." While Jupiter is equal in size to 
over one thousand two hundred earths, Saturn is 
equal to about seven hundred earths. And while 
Jupiter is equal in weight to three hundred 



2 20 Sun, Moon, and Stars. 

earths, Saturn is only equal in weight to ninety 
earths. He appears to be made of very light ma- 
terials — not more than three-quarters as dense as 
water. This would show the present state of 
Saturn to be very different from the present state 
of the earth. We are under the same uncertainty 
in speaking of Saturn as in speaking of Jupiter. 
Like Jupiter, Saturn is covered with dense masses 
of varying clouds, occasionally opening and allow- 
ing the astronomer peeps into lower cloud-levels, 
but rarely or never permitting the actual body of 
the planet to be seen. 

The same perplexities also come in here, to be 
answered much in the same manner. 

We should certainly expect that in a vast 
globe like Saturn the strong force of attraction 
would bind the whole into a dense solid mass. 

Instead of which Saturn is much the least solid 
of all the planets. He seems to be made up of a 
very light substance, surrounded by vapor. 

One explanation can be offered. What if the 
globe of Saturn be still in a red-hot molten state, 
keeping such water as would otherwise lie in 
oceans on his surface floating aloft in masses of 
steam, the outer parts of which condense into 
clouds ? 



Saturn. 221 

No one supposes that Jupiter and Saturn are 
in the same condition of fierce and tempestuous 
heat as the sun. They may have been so once, 
but they must now have cooled down very many 
stages from that condition. Though no longer, 
however, a mass of far-reaching flames and fiery 
cyclones, the body of each may have only so far 
cooled as to have reached a stage of dull molten 
red heat, keeping all water in the form of vapor, 
and sending up strong rushes of burning air to 
cause the hurricanes which bear to and fro the 
vast cloud-masses overhead. 

The diameter of the largest moon is about half 
the diameter of the earth, or much larger than 
Mercury. The four inner satellites are all nearer 
to Saturn , than our moon to us, though the most 
distant of the eight is ten times as far away. 
The inner moon takes less than twenty-three 
hours to travel round Saturn, and the outer one 
over seventy-nine days. 

A great many charming descriptions used to 
be - worked up, with Saturn as with Jupiter, re- 
specting the magnificent appearance of the eight 
radiant moons, joined to the glorious shining of 
the rings, as quite making up for the diminished 
light and heat of the sun. But undoubtedly 



222 Sun, Moon, and Stars. 

Saturn's cloudy covering would much interfere 
with observations of the moons by any inhabi- 
tants of the solid body within — supposing there 
were any solid body at all. And though it sounds 
very wonderful to have eight moons instead of 
one moon, yet all the eight together give Saturn 
only about one-sixteenth part of the light which 
we receive from our one full moon — so much 
more dimly does the sun light them up at that 
enormous distance. 

One more possible proof of Saturn's half- 
liquid state is to be found in his occasional very 
odd changes of shape. Astronomers have been 
startled by a peculiar bulging out on one side, 
taking off from his roundness and giving a 
square-shouldered aspect. 

We may not, perhaps, count it impossible that 
a solid globe should undergo such tremendous 
upheavals and outbursts as to raise a great portion 
of its surface five or six hundred miles above the 
usual level — the change being visible at a dis- 
tance of eight hundred millions of miles. It is, 
however, far easier to understand the possibility of 
such an event in the case of a liquid seething 
mass than in the case of a solid ball. 

On the other hand this alteration of outline 



Saturn. 223 

may be caused simply by a great upheaval, not of 
the planet's surface, but of the overhanging layer 
of clouds. 

Some such changes, only much slighter, have 
been remarked in Jupiter. 

And now as to the rings. Nothing like them 
is to be seen elsewhere in the Solar System. 

They are believed to be three in number, 
though some would divide them into more than 
three. Passing completely round the whole body 
of Saturn, they rise, one beyond another, to a 
height of many thousands of miles. 

The inner edge of the inner ring — an edge 
perhaps one hundred miles in thickness — is more 
than ten thousand miles from the surface of 
Saturn, or more strictly speaking, from the outer 
surface of Saturn's cloudy envelope. A man 
standing exactly on the equator and looking up, 
even if no clouds came between, would scarcely 
be able to see such a slender dark line at such a 
height. 

This dark transparent ring, described as dusky 
or purple, and known as the Crape Ring, rises up- 
wards to a height or breadth of nine thousand 
miles. Closely following it is a ring more bril- 



224 Sun, Moon, and Stars. 

liant than Saturn himself, over eighteen thousand 
miles in breadth. When astronomers talk of the 
" breadth " of these rings it must be understood 
that they mean the width of the band measured 
upwards, in a direction away from the planet. 

Beyond the broad bright ring is a gap of about 
one thousand seven hundred miles. Then follows 
the third ring, ten thousand miles in breadth, its 
outermost edge being at a height of more than 
forty-eight thousand miles from Saturn. The 
color of the third ring is grayish, much like the 
gray marking often seen on Saturn. 

At one time it was supposed that these rings 
were solid, but they are now believed to consist of 
countless myriads of meteorites, each whirling in 
its own appointed pathway round the monster 
planet. 

As already said — leaving out of the question 
the cloudy atmosphere — a man standing on the 
equator would see nothing of the ring. A man 
standing at the north pole or the south pole of 
Saturn could see nothing either, since the rings 
would all lie below his horizon. But if he trav- 
elled southward from the north pole, or northward 
from the south pole, towards the equator, he 
would in time see the ringed arch appearing 




DONATI'S COMET, 1868. 



Sun, Moon and Stabs, 



p. 294. 



Saturn. 225 

above the horizon, rising higher and growing 
wider with every mile of his journey. And when 
he was in a position to view the whole broad ex- 
panse, the transparent half-dark belt below, the 
wide radiant band rising upwards over that, and 
the grayish border surmounting all, he would truly 
have a magnificent spectacle before him. 

This magnificent spectacle is however by no 
means always visible, even from those parts of 
Saturn where alone it ever can be seen. The 
rings shine merely by reflected sunlight. Neces- 
sarily, therefore, while the sunbeams make one 
side bright the other side is dark ; and not only 
this, but the rings throw broad and heavy shadows 
upon Saturn in the direction away from the sun- 
light. 

In the daytime they probably give out a faint 
shining something like our own moon when seen 
in sunlight. During the summer nights they 
shine, no doubt, very beautifully. During the 
winter nights it so happens that their bright side 
is turned away ; and not only that, but during the 
winter days the rings, while giving no light them- 
selves to the wintry hemisphere of Saturn, com- 
pletely hide the sun. 

When it is remembered that Saturn's winter — 

Sun, Moon, etc. I C 



226 Sun, Moon, and Stars. 

that is, the winter of each hemisphere in turn — 
lasts during fifteen of our years, and when we 
hear of total eclipses of the sun lasting unbroken 
through eight years of such a winter, with not 
even bright rings to make up for his absence, we 
cannot think of Saturn as a tempting residence. 
The sun gives Saturn at his best only about one- 
ninetieth of the heat and light that he gives to 
our earth ; but to be deprived of even that little 
for eight years at a time does indeed sound some- 
what melancholy. 

Any one looking from one of the nearer moons 
might have splendid views of Saturn and his rings 
in all their varying phases. 

For Saturn is a beautiful globe wrapped in his 
changeful envelope of clouds, which, seen through 
a telescope, are lit up often with rainbow tints of 
blue and gold, a creamy white belt lying usually 
on the equator, while around extend the purple 
and shining and gray rings, sometimes rivalling 
in bright colors Saturn himself. 

The moons of Saturn do not, like those of 
Jupiter, travel in one plane 



Uranus mid Neptune. 227 



CHAPTER IX. 



URANUS AND NEPTUNE. 



" He hath showed His people the power of His works." — 
Psa. 111:6. 

Till the year 1781 Saturn was believed to be 
the outermost planet of the Solar System, and no- 
body suspected the fact of two great lonely bro- 
ther-planets travelling round the same sun at vast 
distances beyond. 

Uranus, nine hundred millions of miles from 
Saturn. Neptune, one thousand millions of miles 
from Uranus. No wonder they remained long 
undiscovered ! 

Uranus can sometimes be seen by the unaided 
eye as a dim star of the sixth magnitude. And 
when he was known for a planet it was found 
that he had been often so seen and noted. Again 
and again he had been taken for a fixed star, and 
as he moved and disappeared from that particular 
spot it was supposed that the star had vanished. 

One night when Herschel was busily explo- 
ring with a powerful telescope he noticed some- 
thing which he took for a comet without a tail. 



228 Sun, Moon, and Stars. 

He saw it was no mere point of light like the stars, 
but had a tiny round disc or face, which could be 
magnified. So he watched it carefully and found 
in the course of a few nights that it moved — very 
slowly certainly, but still it did move. Further 
watching and calculation made it clear that, 
though the newly-found heavenly body was at a 
very great distance from the sun, yet it was 
moving slowly in an orbit round the sun. Then it 
was known to be a planet and another member of 
the Solar System. 

Everybody supposed that now at least the out- 
ermost member of all was discovered. 

But a very strange and remarkable thing hap- 
pened* 

Astronomers know with great exactness the 
paths of the planets in the heavens. They can 
tell, years beforehand, precisely what spot in space 
will be filled at any particular time by any par- 
ticular planet. I am speaking now of their move- 
ments round the sun and in the Solar System — not 
of the movements of the whole family with the 
sun, about which little is yet known. 

Each planet has its own particular pathway ; 
its own particular distance from the sun, varying 
at each part of its pathway ; its own particular 



Uranus and Neptune. 229 

speed in travelling round the sun, changing con- 
stantly from faster to slower or slower to faster 
according to its distance from the sun and accord- 
ing to the pull backwards or forwards of other 
neighboring planets in front or in rear. 

For as the orbits of all the planets are ovals, 
with the sun not in the middle, but somewhat to 
one side of the middle, it follows that all the 
planets in the course of their years are some- 
times nearer to and sometimes farther from the 
sun. 

The astronomers of the present day under- 
stand this well, and can describe with exactness 
the pathway of each planet. This knowledge 
does not come merely from watching one year 
how the planets travel and remembering for 
another year, but is much more a matter of close 
and difficult calculation. 

It seems to be the will of God to govern com- 
monly things in the heavens as He governs com- 
monly things upon earth, by certain regular laws 
of working. " Laws of nature " we call them, 
though "laws of God " would perhaps be a truer 
expression and reach higher. 

There was a greaY astronomer, named Kepler, 
who discovered some of the wonderful laws by 



230 Sun, Moon, and Stars. 

which God governs the movements of the plan- 
ets in their orbits. " Kepler's Three Laws " are 
often spoken about, by which is meant " three 
laws of God's working in nature discovered by 
Kepler." 

Before these laws and others were understood 
the movements of the planets were a constant 
puzzle. Now that they have been clearly grasped, 
astronomers can not only perceive, as it were, the 
plan of all the planets' journeys, but can draw out 
beforehand a scheme or sketch, according to these 
laws, telling exactly what the pathway of any one 
planet is sure to be. 

Many things have to be considered, such as 
the planet's distance from the sun, the sun's 
power of attraction, the planet's speed, the near- 
ness and weight of other neighboring planets. 

All these questions were gone into and astron- 
omers sketched out the pathway in the heavens 
which they expected Uranus to follow. He would 
move in such and such an orbit, at such and such 
distances from the sun, and at such and such rates 
of speed. 

But Uranus would not keep to these rules. He 
quite discomfitted the astronomers. Sometimes he 
went fast when according to their notions he 



Uranus and Neptune. 231 

ought to have gone more slowly ; and sometimes 
he went slowly when they would have looked for 
him to go more fast, and the line of his orbit was 
quite outside the line of the orbit which they 
had laid down. He was altogether a perplexing 
acquaintance and difficult to understand. How- 
ever, astronomers felt sure of their rules/and 
modes of calculation, so often before tested and 
not found to fail. They made a guess at an 
explanation. What if there were yet another 
planet beyond Uranus, disturbing his motions, 
now drawing him on, now dragging him back, 
now so far balancing the sun's attraction by pull- 
ing in the opposite direction as to increase the 
distance of Uranus from the sun ? 

It might be so. Yet who could prove it? 
Hundreds of years might pass before any astron- 
omer in his star-gazing should happen to light 
upon such a dim and distant world. Nay, the 
supposed planet might be, like Uranus, actually 
seen, and only be mistaken for a "variable star," 
shining but to disappear. 

There the matter seemed likely to rest. There 
the matter probably would have rested for a good 
while had not two men set themselves to conquer 
the difficulty. One was a young Englishman, 



232 Sun, Moon, and Stars. 

John Couch Adams; the other a young French- 
man, Leverrier — both being astronomers. 

Each worked independently of the other, nei- 
ther knowing of the other's toil. The task which 
they had undertaken was no light one — that of 
reaching out into the unknown depths of space to 
find an unknown planet. 

Each of these silent searchers into the sky- 
depths calculated what the orbit and speed of 
Uranus would be without the presence of another 
disturbing planet beyond. Each examined what 
the amount of disturbance was, and considered 
the degree of attraction needful to produce that 
disturbance, together with the direction from 
which it had come. Each, in short, gradually 
worked his way through calculations far too deep 
and difficult for ordinary minds to grasp till he 
had found just that spot in the heavens where a 
planet ought to be to cause, according to known 
laws, just such an effect upon Uranus as had been 
observed. 

Adams finished his calculation first, and sent 
the result to two different observatories. Unfor- 
tunately his report was not eagerly taken up. It 
was, in fact, hardly believed. Leverrier finished 
his calculation also and sent the result to the 



Uranus and Neptune, 233 

Berlin observatory. The planet was actually seen 
in England first, but the discovery was actually 
made known from Berlin first. The young Eng- 
lishman had been beforehand, but the young 
Frenchman gained foremost honor. 

This, however, was of slight comparative im- 
portance. The truly wonderful part of the matter 
was that these two men could have so reasoned 
that, from the movements of one lately-discovered 
planet, they could point out the exact spot where 
a yet more distant planet ought to be, and that 
close to this very spot the planet was found. 

For when both in England and in Germany 
powerful telescopes were pointed in the direction 
named, there the planet was.' 

No doubt about the matter. Not a star, but a. 
real new planet in the far distance, wandering 
slowly round the sun. 

This was indeed a triumph of human intellect. 
Yet it is no matter for human pride, but rather of 
thankfulness to Him who gave to man this mar- 
vellous reasoning power. And the very delight 
we have in such a success may humble us in the 
recollection of the vast amount lying beyond of 
the utterly unknown. 

Perhaps the chief feeling of satisfaction in this 



234 Sun, Moon, and Stars. 

particular discovery may be said to arise from the 
fact that it gives marked and strong proof of the 
truth of our present astronomical system and be- 
liefs. Many mistakes may be made and much has 
often to be unlearned. Nevertheless, if the gen- 
eral principles of modern astronomy were wrong,- 
if the commonly-received facts were a delusion, 
such complete success could not have attended so 
delicate and difficult a calculation. 

We do not know much about these two outer 
planets, owing to their enormous distance from us. 

Uranus is in size equal to sixty-four earths, 
and Neptune is in size somewhat larger than 
Uranus. Both these planets are formed of deci- 
dedly heavier materials than Saturn, being about 
as dense as water. 

The size of the sun as seen from Uranus is 
about one three-hundred-and-ninetieth part of the 
size of the sun we see. To Neptune he shows a 
disc only one nine-hundredth part of the size of 
that visible to us — no disc at all, in fact, but only 
star-like brilliancy to any such eyes as ours. 

The Uranian year lasts about eighty-four of 
our years ; and this, with a very sloping axis, 
must cause most long and dreary winters, the 



Uranus and Neptune. 235 

tiny sun being hidden from parts of the planet 
during half an earthly lifetime. 

Uranus has at least four moons, travelling in 
very different planes from the plane of the eclip- 
tic. Once it was thought that he had eight, but 
astronomers have since searched in vain for the 
other four believed for a while to exist. Nep- 
tune has one moon and may possess others not 
yet discovered. 



236 Sun, Moon, and Stars. 



CHAPTER X. 

COMETS AND METEORS. 
" It is the glory of God to conceal a thing." Prov. 25 : 2. 

An interesting discovery has been made. It 
appears that some sort of mysterious tie exists be- 
tween comets and meteors. 

For a long while this was never suspected. 
How should it be ? The comets so vast in size, 
the meteors so small and evanescent— how could 
it possibly be supposed that the one had anything 
to do with the other ? 

But supposings often have to give in to facts. 
Astronomers have gradually become convinced 
that there certainly is a connection between the 
two. 

Comets and meteor-streams are found to occu- 
py, sometimes at least, the very same pathways in 
the heavens, the very same orbits round the sun. 
A certain number of meteor-systems are now 
pretty well known to astronomers as regularly 
met by our earth at certain points in her yearly 
journey. Some of these systems or rings have 



Comets and Meteors. 237 

each a comet belonging to it — not merely journey- 
ing near, but actually in its midst, on the same 
orbit. 

Perhaps it would be more correct to say that 
the meteors belong to the comet than that the 
comet belongs to the meteors. We tread here on 
uncertain ground ; for whether the meteors spring 
from the comet or whether the comet springs 
from the meteors or whether both spring from 
the same source, cannot yet be quite definitely 
asserted. 

Though we cannot fully explain the kind of 
connection, yet a connection there plainly is. So 
many instances are now known of a comet and a 
meteor-ring travelling together that it is doubtful 
whether any such ring could be found without a 
comet in its midst. By-and-by the doubt may 
spring up whether there ever exists a comet with- 
out a train of meteors following him. 

Among the many different Meteor-Rings which 
are known, two of the most important are the so- 
called August and November systems. Of these 
two the November system must claim our chief 
attention. 

Not that we are at all sure of these being the 



238 Sun, Moon, and Stars. 

most important meteor-rings in the Solar System. 
On the contrary, as regards the November ring, 
we have some reason to think that matters may 
lie just the other way. 

The comet belonging to the November system 
is a small one, quite an insignificant little comet, 
only visible through a telescope. We do not of 
course know positively that larger comets and 
greater meteor systems generally go together; 
but to say the least it seems likely. And if the 
greatness of a ring can at all be judged of by the 
size of its comet, then the November system must 
be a third-rate specimen of its kind. It is of par- 
ticular importance to us merely because it hap- 
pens to be the one into which our earth plunges 
most deeply, and which we therefore see and 
know the best. The August ring is on the con- 
trary connected with a magnificent comet, and 
may be a far grander system. But our pathway 
does not lead us into the midst of the August me- 
teors as into those of November. We pass seem- 
ingly through its outskirts. 

The meteors of the November system are very 
small. They are believed to weigh commonly 
only a few grains each. If they were larger and 
heavier, some of them might find their way to 



Comets and Meteors. 239 

earth's surface only half diminished in their rush 
through the air; but this they seem never to 
do. 

Doubtless Meteor-Systems exist in the Solar 
System which our earth does not encounter, con- 
taining much larger and heavier meteors. It is 
well for us that we do not plunge into any such 
ring, or we might find our atmosphere an insuffi- 
cient protection. 

The last grand display of the November sys- 
tem of meteorites took place in the years 1866 to 
1869, being continued more or less during three 
or four Novembers following. The next grand 
display is not expected until the year 1899. 

For this system — Leonides, as it is called * — 
seems to have a " time " or " year " of thirty-three 
and a quarter earthly years. 

The shape of its orbit is a very long ellipse, 
near one end of which is the sun, while the other 
end is believed to reach farther away than the 
orbit of Uranus. 

A great deal of curiosity has been felt about 
the actual length and breadth and depth of the 

* Because the falling-stars in this display seem all to shoot 
towards us from a spot in the constellation Leo, 



240 Sun, Moon, and Stars. 

stream of meteorites through which our solid 
earth has so often ploughed her way. 

during many hours at a time lookers-on have 
watched the magnificent display of heavenly fire- 
works — not a mere shooting-star here and there 
as on common nights, but radiant meteors flash- 
ing and dying by thousands through the sky. In 
1 866 no less than eight thousand meteors in two 
hours and a quarter were counted from the Green- 
wich Observatory. A natural wonder sprang up 
in many minds as to the extent of the ring from 
which they fell. 

For not in one night only, but in several 
nights during three or four years, and that not 
once only, but once in every thirty-three years, 
thousands and tens of thousands appear to have 
been stolen by our earth from the meteor-ring, 
never again to be restored. Yet each time we 
touch the ring we find the abundance of little 
meteors in no wise seemingly lessened. 

When speaking of a " ring " of meteors it must 
not be supposed that necessarily the meteors form 
a whole unbroken ring all round the long oval 
orbit. There may be no breaks. There may be a 
more or less thin scattering throughout the entire 
length of the pathway. But the meteors cer- 



Comets and Meteors. 241 

tainly seem to cluster far more densely in some 
parts of the orbit than in other parts, and it was 
about the size of the densest cluster that so m h 
curiosity was felt. 

Little can be positively known, though it is 
very certain that the cluster must be enormous in 
extent. Three or four years running, as our 
earth, after journeying the whole way round the 
sun, came again to that point in her orbit where 
she passes through the orbit of the Leonides, she 
found the thick stream of meteors still pouring 
on, though each year lessening in amount. Ta- 
king into account this fact, and also the numbers 
that were seen to fall night after night, and also 
the speed of our earth, a " rough estimate " was 
formed. 

The length of this dense cluster is supposed to 
reach to many hundreds of millions of miles. 
The thickness or depth of the stream is calculated 
to be in parts over hundreds of thousands of 
miles, and the breadth perhaps not less than one 
hundred thousand miles. Each meteor is prob- 
ably at a considerable distance from his neigh- 
bors ; but the whole mass of them, when in the 
near neighborhood of the sun, must form a mag- 
nificent sight. And if this be only a third-rate 

Sun, Moon, etc. IQ 



242 Sun, Moon, and Stars. 

system what must a first-rate system be like? 
And how many such systems are there through- 
out the sun's wide domains ? The most powerful 
telescope gives us no hint of the existence of 
these rings till we find ourselves in their midst. 

It may be that they are numbered by thou- 
sands, even by millions. The whole of the Solar 
System— nay, the very depths of space beyond — 
may, for aught we know, be crowded with Meteor 
Systems. Every comet may have his stream of 
meteors following him, but though the comet is 
visible to us, the meteors are not. Billions upon 
billions of them may be ever rushing round our 
sun, entirely beyond our ken, till one or another 
straggler touches our atmosphere to flash and die 
as a " shooting star " in our sight. 

We have, and with our present powers we can 
have, no certainty as to all this. But I may quote 
here the. illustration of a well-known astronomical 
writer on the subject. 

Suppose a blind man were walking out of 
doors along a high-road, and during the course of 
a few miles were to feel rain falling constantly 
upon him. Would it be reasonable on his part if 
he concluded that a small shower of rain had ac- 
companied him along the road as he moved, but 



Comets and Meteors. 243 

that fine weather certainly existed on either side 
of the road ? On the contrary, he might be sure 
that the drops which he felt were but a few 
among millions falling all together. 

Or look at the rain-drops on your window 
some dull and rainy day. Count how many there 
are. Could you, with any show of common-sense, 
decide that those rain-drops, and those alone, 
had fallen that day in your town ? 

So when we find these showers of meteors 
falling to earth we may safely conclude that, for 
every one which touches our atmosphere, myriads 
rush elsewhere in space, never coming near us. 



244 Sun, Moon, and Stars. 



CHAPTER XI. 

MORE ABOUT COMETS AND METEORS. 
" He commanded, and they were created." — Psa. 148 : 5. 

There have been several comets of import- 
ance seen in the present century. 

In 181 1 a remarkably fine one appeared. The 
bright nucleus was only about four hundred miles 
in diameter, but the whole head, including the 
envelope or coma, measured one hundred and 
twelve thousands of miles across, and the enor- 
mous tail stretched out to a distance of one hun- 
dred and twelve millions of miles. This comet 
travels in so long and narrow an ellipse that some 
say his return must not be looked for in less than 
thirty centuries. 

The great comet which in 1682 received first 
the name of Halley's Comet appeared last in 1835, 
his return having been foretold within three days 
of its actually taking place. For Halley's Comet is 
a member of the Solar System having a yearly 



More About Comets and Meteors. 245 

¥ — , 

journey of seventy -six earthly years. He jour- 
neys nearer to the sun than Venus and travels 
farther away than Neptune. 

In 1843 appeared one of the brightest comets 
ever seen, and also one of the nearest to the sun. 
So close ran his orbit to the centre of our system 
that at one time his nucleus was only about thirty 
thousand miles from the sun's surface. When we 
remember that sun-flames often rise to a height 
of more than fifty thousand miles we shall see 
how terrific must have been the heat en- 
dured. 

In the years 1858, 1861, and 1862 three more 
comets appeared, all visible without the help of a 
telescope. Of these three, Donati's Comet, in 
1858, was far superior to the rest. 

It was a singular fact about the comet of 1858 
that at one time the star Arcturus could be seen 
shining through the densest portion of the tail, 
close to the nucleus. Now, although the faintest 
cloud-wreath of earth would dim if not hide this 
star, yet the tail of the comet was of so trans- 
parent a nature that Arcturus shone un dimmed, 
as if no veil had come between. The exceedingly 
slight and airy texture of a comet's tail could 
hardly be more plainly shown. 



246 Sun, Moon, and Stars. 
% __ 

It was this gauzy appendage to a little nucleus 
which men once thought could destroy our solid 
earth at a single blow ! 

Yet, while taking care not to overrate, we must 
not underrate. True, the comets are delicate and 
light in structure. One comet, in 1770, wandered 
into the very midst of Jupiter's moons, and so small 
was its weight that it had no power whatever, so 
far as has been detected, to disturb the said moons 
in their orbits. Jupiter and his moons did very 
seriously disturb the comet, however; and when 
he came out from their midst, though none the 
worse for his adventure, he was forced to travel in 
an entirely new orbit, and never managed to get 
back to his old pathway again. 

But there are comets and comets, some being 
heavier than others. The comet named after 
Donati, albeit too transparent to hide a star, was 
yet so immense in size that his weight was calcu- 
lated by one astronomer to amount to as much as 
a mass of water forty thousand miles square and 
one hundred and nine yards deep. 

When first noticed, Donati's Comet had, like all 
large comets, a bright envelope of light round the 
nucleus. After a while the one envelope grew 
into three envelopes and a new tail formed beside 



More Abotct Comets and Meteors. 247 

the principal tail, which for a time was seen to 
bend gracefully into a curve like a splendid plume. 
A third but much fainter tail also made its appear- 
ance, and many angry-looking jets were poured 
out from the nucleus. These changes took place 
while the comet was passing through the great 
heat of near neighborhood to the sun. After- 
wards, as he passed away, he seemed gradually to 
cool down and grow quiet. 

The singular changes in the appearance of 
Newton's Comet have been earlier noticed. No 
marvel that he did undergo some alterations. 
The tremendous glare and burning heat which 
that comet had to endure in his rush past the sun 
were more than twenty-five thousand times as 
much as the glare and heat of the fiercest tropical 
noonday ever known upon earth. Can we wonder 
that he should have shown " signs of great excite- 
ment/' that his head should have grown larger 
and his tail longer ? 

It certainly was amazing and bewildering that 
the said tail, over ninety millions of miles in 
length, should in four days have seemingly swept 
round in an enormous half-circle, so as first to 
point in one direction and then to point in just 
the opposite direction. 



248 Sun, Mo oti) and Stars. 

We are much in the habit of speaking about 
comets as travelling through the heavens with 
their tails streaming behind them. But though 
this is sometimes the case it is not always so. 

The tails of comets always stream away from 
the sun, whether before or behind the comers head 
seeming to be a matter of indifference. 

As the comet comes hurrying along his orbit 
with ever-increasing speed towards the sun, the 
head journeys first and the tail follows after. 

But as the comet rounds the loop of his orbit 
near the sun — the point nearest of all being called 
his perihelion — the head always remains towards 
the sun, while the tail swings, or seems to swing, 
in a magnificent sweep round, pointing always in 
the direction just away from the sun. 

Then, as the comet journeys with slackening 
speed on the other side of his orbit, towards the 
distant aphelion or farthest point from the sun, he 
still keeps his head towards the sun. So at this 
part of his passage, in place of the head going first 
and the tail following after, the tail goes first and 
the head follows after. The comet thus appears 
to be moving backwards. Or, like an engine push- 
ing instead of drawing a train, the head seems to 
be driving the tail before it. 



More About Comets and Meteors. 249 

This careful avoidance of the sun by comets' 
tails is remarkable. Astronomers speak of the 
" repulsive energy " with which the sun "sweeps 
away" from his neighborhood the light gauzy 
appendages of a comet ; but the precise nature of 
that repulsion and the mode of its working are not 
yet manifested. 

It need not be supposed that the enormous 
tails, millions of miles in length, are formed of 
unbroken and connected substance, whirled round, 
like a vast kite-tail or a stupendous fan, at a per- 
fectly unimaginable speed. The actual make of 
the tails cannot yet be stated with certainty ; but 
there is a growing belief among astronomers that 
electricity may have something of a hand in the 
matter. 

After all, the tail is a mere adjunct to the 
comet — no more needful to a comet's existence 
than a man's beard is to the man's existence. 
According to ordinary notions, a full-blown comet 
consists of the bright central nucleus, the sur- 
rounding coma, and the far-reaching tail. But if 
you have the nucleus you have the comet, and no 
more is necessary. It is known to be a comet, not 
a star, mainly by the path that it follows and the 
rates of its motions. 



250 Sun, Moon, and Stars. 

The coma has been described by Dr. Huggins 
as " usually a luminous fog, surrounding the nu- 
cleus and gradually shading off from it ;" and the 
tail as " a continuation, in a direction opposite to 
that of the sun, of the luminous fog of the coma." 

Except in the sun's neighborhood a comet's 
tail has commonly no existence. As the wanderer 
draws near to our luminary, a tail of less or greater 
dimensions is often developed under the increasing 
heat : and as the wanderer passes away once more 
the tail diminishes and disappears. 

Spectrum analysis declares that comets usually 
consist of carbon, hydrogen, nitrogen, and possibly 
oxygen — all, of course, in a state of highly -heated 
and light-emitting gas. To some extent also a 
comet reflects the sunlight. 

More than this is known of the nature of 
comets through studying the nature of their near 
of kin — meteors and meteorites. Speaking at the 
same time as just cited, Dr. Huggins said further, 
" We are thus led to see the close physical connec- 
tion and oneness of origin, if not indeed identity 
of nature, of comets and of these meteors. Now, 
the meteors on these occasions " — the great meteor 
showers — " are too minute to pass through the 
ordeal of ignition by our atmosphere : they are 



More About Comets and Meteors. 251 

burned up before they reach the earth : but at 
other times small celestial masses come down to 
us which, there can be little doubt, are of the same 
order of bodies and similar in chemical nature." 

Here again spectrum analysis steps in and tells 
us that in the make of celestial meteorites falling 
to earth, among divers other substances may be 
found the hydrogen, carbon, and nitrogen which 
we have already seen to be the main substances in 
the composition of comets. 

True, a fallen meteorite is small, solid, heavy, 
while a comet is light and hazy. But if the mate- 
rials of which a meteorite is made were rendered 
gaseous, then at once it would be not only much 
larger, but light and hazy. 

In 1867 a large lecture-room was entirely 
lighted by means of gas extracted from a meteor- 
ite which had arrived from distant space. 

Not only do solid aerolites fall half -burned to 
the ground, but even when the meteorites are 
quite consumed in the air the fine dust remaining 
still sinks earthward. This fine dust has been 
found upon mountain-tops, and has been proved 
by close examination to be precisely the same as 
the material of the solid aerolites. 

It is a wonderful thought that we should real- 



252 Sun, Moon, and Stars, 

ly have these visitants from the sky, solid metal 
or showers of dust coming to us frdtn distant 
space. 

If the dust of thousands of meteorites is always 
thus falling earthward, one would imagine that it 
must in time add something to the weight of the 
earth. And this actually is the case. During the 
last three thousand years no less than one million 
tons of meteorite-dust must, according to calcula- 
tion, have fallen to earth out of the sky. A mil- 
lion tons is of course a mere nothing compared 
with the size of the world. Still the fact is curious 
and interesting. 

Some of the tremendous outbursts seen on the 
surface of the sun have been described earlier. It 
is believed that in such outbursts matter is driven 
forth with violence sufficient to send it whirling 
through space, never to return thither. Many 
meteorites may have had their birth thus, whether 
from our own sun or from stars like in nature to 
our sun. 

It has been conjectured that some meteorites 
may also have sprung from earthly volcanoes, 
being shot aloft with impetus enough to carry 
them to a vast distance, breaking loose perhaps 
for a while from earth's control, but after a length- 



More About Comets and Meteors. 253 

ened period— it may be accidentally — travelling 
earthward once more. 

A few more words about " comet- visitors/ * 

Many comets, as stated earlier, belong to the 
Solar System ; but many also come only once, 
flashing round the sun and rushing away in a 
new direction, never to return. Any comet at 
about the distance of our earth from the sun, trav- 
elling at a rate of more than twenty-six miles per 
second, is beyond solar control. The sun is power- 
less to hold prisoner so impulsive a vagrant, and it 
must find its way out of the Solar System. 

Comets which come to us from outside our 
System must come from some other System. And 
the nearest Systems known are those of the stars. 

The nearest star of all, among those whose 
distance has yet been measured, is Alpha Cen- 
tauri. A comet passing from Alpha Centauri to 
our Solar System would require millions of years 
for his journey. But it is not impossible that other 
stars may lie nearer to us than Alpha Centauri, 
although the fact has not yet been discovered. 

END OF PART II. 



PART III. 



Many Suns. 257 



CHAPTER I 



MANY SUNS. 



"I, even my hands, have stretched out the heavens, and all 
their host have I commanded." Isa. 45 : 12. 

Once more we have to wing our flight far far 
away from the busy Solar System where we live ; 
away from whirling planets, moons, meteorites, all 
shining with reflected sunlight ; away from the 
great central sun himself, our own particular 
bright star. Once more we have, in imagination, 
to cross the vast black empty space — is it black? 
and is it empty? had we sight to see things as 
they are — separating our sun from other suns, our 
star from other stars. 

For the sun is a star — only a star. And stars 
are suns— big blazing suns. One is near and the 
others far away, that is the main difference. 

We have no longer to do with bodies merely 
reflecting another's light — always dark on one 
side and bright on the other — but with burning 
bodies, shining all around by their own light. 
We have no longer to picture just one single 
star with his surrounding worlds, but we have to 
17 



258 Sun, 'Moon, and Stars. 

fix our thoughts upon the great universe of stars 
or suns in countless millions. 

The sun is centre and ruler and king in his 
own system. But as a star he is only one among 
many stars, some greater, some less than himself. 

Thought travels fast, faster than a comet, fast- 
er than light. A rushing comet would, it is be- 
lieved, take eight millions of years to cross the 
chasm between the nearest known fixed star and 
us. Light, flashing along at the rate of about 
186,300 miles a second, will perform the same 
journey in four years and one-third. But thought 
overleaps the boundary in less than four minutes. 

Each star that we see in the heavens is to our 
eyesight simply one point of light. The brighter 
stars are said to be of greater magnitude, and the 
fainter stars of lesser magnitude, yet one and all 
they have no apparent size. The most powerful 
telescope, though it can increase their brilliancy, 
cannot add to their size. A planet which to the 
naked eye may look like a star will, under a tele- 
scope, show a disc the breadth of which can be 
measured or divided ; but no star has any real 
sensible disc in the most powerful telescope yet 
constructed. 



Many Suns. 259 



The reason of this is the enormous distance 
of the stars. Far off as many of the planets lie, 
yet the farthest of them is as a member of our 
household compared with the nearest star. 

I have already tried to make clear the fact of 
their vast distance. Light, which comes to us 
from the sun in less than nine minutes, takes four 
years and four months to reach us from Alpha 
Centauri. From this four-years-and-a-half length 
of journey between Alpha Centauri and Earth the 
numbers rise rapidly to twenty years, fifty years, 
hundreds of years, even thousands of years. The 
distances of most of the stars are completely be- 
yond our power to measure. The whole orbit of 
our earth, nay, the whole wide orbit of the far-off 
Neptune, would dwindle down to one single point, 
if seen from the greater number of the stars. 

It used to be believed that, taking the stars 
generally, there was probably no very marked 
difference in their size, their kind, their bright- 
ness. Some of course would be rather larger and 
others rather smaller ; still it was supposed that 
they might be roughly classed as formed much on 
the same scale and the same plan. But of late 
years this notion has been utterly given up. 



260 Sun y Moon, and Stars. 

A very similar idea used to be held with re- 
gard to the Solar System. The wonderful variety 
of form and richness in numbers now known to 
abound within its limits are discoveries of later 
years ; and now the same variety in kind and size 
is found also among the stars. The more we look 
into the heavens the more we see that dull blank 
uniformity is not to be found there. 

It is the same upon earth. Man builds his 
little rows of box-like houses side by side, each 
one exactly like all the rest, or dresses his thou- 
sand soldiers in coats of the same cut and color, or 
repeats a neat leaf-design hundreds of times on 
carpets or wall-papers. But God never makes 
two leaves or two blades of grass alike. Whole- 
sale turning out of things after one pattern is 
quite a human idea, not divine. 

We know so much about the stars as that some 
are at least considerably larger and some consider- 
ably smaller than others. 

When one star is seen to shine brightly and 
another beside it shines dimly, we are apt to think 
that the brightest must be the nearest. Yet it is 
often impossible for us to say how much of the dif- 
ference is owing to the greater distance of one or 



Many Suns. 261 



the other, to the greater size of one or the other, 
or to the greater brilliancy of one or the other. 

In many instances we do know enough to be 
quite sure that there is a great difference, not 
only in the distance of the stars, but in their size, 
their kind, their brightness. 

The stars have been sometimes classed into 
four distinct orders or degrees — partly depending 
on their color. 

The first class is that of the White Suns. These 
are generally held to be the grandest and might- 
iest of all. The star Sirius belongs to the order 
of White Suns. 

Secondly comes the class of Golden Suns. To 
these blazing orbs of yellow light, said to be 
second only to the white-light stars, belongs our 
own sun. 

Thirdly, there are numbers of stars called 
Variable Stars, the light of which is constantly 
changing, now becoming greater, now becoming 
less. 

Fourthly, there is the class of small Red Suns, 
about which not so much is known. 

These four orders or divisions do not by any 
means include all the stars, or even all the single 
stars. Roughly speaking, however, the greater 



262 Sun, Moon, and Stars. 

number of single stars, and many also of the 
double stars, belong to one or another of the above 
classes. 

When we talk of the different sizes of the 
different stars it should be plainly understood 
that we have no means of directly measuring 
them. A point of light showing no disc, no sur- 
face, no breadth, cannot be measured, for there is 
nothing to measure. 

In certain cases we are not entirely without 
the power of judging. The distances of some of 
the stars from us have been found out. Knowing 
how far off any particular star is, astronomers are 
able to calculate exactly how bright our own sun 
would look at that same distance. If they find 
that our sun would shine just as the star in ques- 
tion shines, there is some reason for supposing 
that our sun and yonder star may be of the same 
size. If our sun would shine more brightly than 
the star shines, there is some reason for supposing 
that the star may be smaller than our sun. If 
our sun would shine more dimly than the star 
shines, there is some reason for supposing that 
the star may be larger than our sun. 

Other matters, however, have to be considered. 
Suppose we find a star at a certain distance shi- 



Many Suns. 263 



ning twice as brilliantly as our own sun would 
shine at that same distance. Naturally then we 
say that star must be much larger than our sun. 

The reasoning may be mistaken. We do not 
know the fact. What if, instead of being a much 
larger sun, it is only a much brighter sun ? 

This is more than possible. Some doubts have 
been, indeed, expressed whether the surface of 
any star could exceed that of our sun in radiance. 
But we have really no reason to suppose that our 
sun is a king of suns in brilliance, since certainly 
he is not so in size or in speed. 

When we picture to ourselves the star-depths, 
the boundless reaches of heavenly space with 
these countless blazing suns scattered broadcast 
throughout, we have not to picture a universe in 
repose. 

On the contrary, all is life, stir, energy. Just 
as in the busy whirl of our Solar System* no such 
thing as rest is to be found, so also it seems to be 
in the wide universe. 

Every star is in motion. ■" Fixed" as we call 
them, they are not fixed. Invisible as their move- 
ments are to our eyes, through immensity of dis- 
tance, yet all are moving. Those silent, placid, 



264 Sun, Moon, and Stars. 

twinkling specks of light are, in reality, huge roar- 
ing, seething, tumultuous furnaces of fire and flame, 
heat and radiance. 

Each, too, is hurrying along his appointed path- 
way in space. Some move faster, some move 
more slowly. One mile per second, ten miles per 
second, twenty, fifty, hundreds of miles per sec- 
ond — thus varying are their rates of speed. 

But whether fast or whether slowly, still on- 
ward and ever onward they press. Some are rush- 
ing towards us, some are rushing away from us. 
Some are speeding to the right, some are speeding 
to the left. 

Where are they going ? Does any single star 
ever return to his starting-point — wherever that 
starting-point may have been? Do they journey 
in vast circles or ellipses round some far-distant 
centre ? What controls them all ? Is it the mighty 
power of some such centre, or does each star by 
his faint and distant attraction help to control all 
his brother-stars, to guide them on their appointed 
path, to preserve the delicate balance of a uni- 
verse ? 

How little we know about the matter ! 

Only so much we can tell — that the controlling 
and restraining hand of God is over the whole. 



Many Suns. 265 



Whether by the attraction of one great centre or 
by the united influences of a thousand fainter at- 
tractions, He steers each radiant sun upon its 
heavenly path, " upholding all things by the word 
of His power/' There is no blundering, no confu- 
sion, no entanglement. All is perfect order, calm 
arrangement, restrained energy. 



266 Sun, Moon, and Stars. 

CHAPTER II. 

SOME PARTICULAR SUNS. 

" The glory of the Lord shall endure for ever : the Lord 
shall rejoice in his works." — Psa. 104 131. 

In the constellation of the Swan there is a little 
dim sixth-magnitude star scarcely to be seen with- 
out a telescope. This star, 61 Cygni by name, is 
the first whose distance from us it was found pos- 
sible to determine. 

We may think it strange that so faint a star 
was even attempted. Would not astronomers 
have naturally supposed it to be one of the far- 
ther-distant stars ? 

No, they did not. For though 61 Cygni showed 
but a dim light, yet his motion — not the daily ap- 
parent motion, but the real motion as seen from 
earth — was found to be so much more rapid than 
the motion of most other stars that they rightly 
guessed 61 Cygni to be a rather near neighbor of 
ours. 

Do not misunderstand me when I speak of 
" more rapid motion " and of " rather near neigh- 
borhood.' 5 



Some Particular Suns. 267 

The real rate of 61 Cygni's rush through space 
is believed to be about thirty-six miles each sec- 
ond, or more than one thousand millions of miles 
each year. All we can perceive of this quick mo- 
tion is that in the course of three hundred and 
fifty years 61 Cygni travels over a space in the sky 
about as long as the breadth of the full moon. 
Little enough, yet far beyond that detected in the 
greater number of even the brightest stars. 

Then again as to the near neighborhood of 
this star, 61 Cygni is near enough to have his dis- 
tance measured, and that is saying a good deal. 
Alpha Oentauri, the nearest star of which we know 
in the southern heavens, is more than two hun- 
dred thousand times as far distant as the sun. But 
61 Cygni, the nearest star of which we know in 
the northern heavens, is nearly twice as far, or 
some forty billions of miles away. 

We call 61 Cygni a star, for so he appears to 
commonobservers. In reality, instead of being only 
one star, the speck of light which we -call 61 Cygni 
consists of two stars. The two are separated by 
a gap about half as wide again as the wide gap 
between the sun and Neptune. Yet so great is 
their distance from us that to the naked eye the 
two seem to be one. 



268 Sun, Moon, and Stars. 

These two suns might together make a sun 
perhaps about one-third as large as our sun. They 
differ in size, the quicker movements of one show- 
ing it to be the smaller ; and it is by means of 
their known distance from one another, and their 
known rate of motion, that their size, or rather 
their weight, can be roughly calculated. Of 
course neither of the two shows any actual meas- 
urable disc. 

So much and so little is with tolerable certainty 
known about this particular pair of suns. 

Next let us turn to Alpha Centauri — named 
Alpha, the first letter of the Greek alphabet, be- 
cause it is the brightest star in the constellation 
of the Centaur. The second brightest star in a 
constellation is generally called Beta, the third 
Gamma, the fourth Delta, and so on ; just as if we 
were to name them A, B, C, D, in order of bright- 
ness. 

The constellation Centaur lies in the southern 
heavens, close to the beautiful constellation called 
the Southern Cross, and is invisible in England. 

Of all the stars shining in the heavens round 
our earth, two only — Sirius and Canopus — show 
greater brilliancy than Alpha Centauri. 



Some Particular Suns. 269 

As in the case of 61 Cygni, astronomers were 
led to attempt the measurement of Alpha Cen- 
tauries distance by noticing how much more dis- 
tinct were his movements than the movements of 
other stars, though less rapid both to the eye and 
in reality than those of 61 Cygni. 

The distance of Alpha Centauri from us is 
more than two hundred thousand times the dis- 
tance of the sun, or about twenty millions of mil- 
lions of miles. In other words, light, travelling 
at the rate of 186,300 miles each second, takes four 
years to journey from Alpha Centauri to Earth. 

And this, so far as we yet know, is our sun's 
nearest neighbor in the heavens outside his own 
family circle. 

Alpha Centauri, like 61 Cygni, is found to con- 
sist, not of a single star, but of a pair of stars. It 
is a two-sun system — whether or no surrounded by 
planets cannot be told. 

The two suns of the Alpha Centauri double- 
star are separated by a distance about twenty-two 
times as great as the distance of the earth from 
the sun, yet to the naked eye they show as a sin- 
gle star. Here again one is much smaller than 
the other ; and the smaller revolves round the 
larger in about eighty-five years. 



2 70 Sun, Moon, and Stars. 

It is supposed that the two together might 
form a sun considerably larger and heavier than 
our sun. This belief is strengthened by the great 
brilliancy of Alpha Centauri. Our own sun, placed 
at that distance from us, would shine only about 
one-third as brightly as he does. 

Turning now from the sun whose distance was 
first measured and from the nearest star with 
which we are acquainted, let us think about the 
most radiant star in the heavens — Sirius, "the 
blazing Dog-star of the ancients,'* named by one 
astronomer " the king of suns." 

„ First, as to the color of Sirius. He belongs 
to the order of " White Suns," and among all the 
white suns known to us Sirius ranks as chief. 
There may be many at greater distances far sur- 
passing him in size and weight and brilliancy ; but 
we can only speak so far as we know. 

One ancient writer spoke of Sirius as " red " 
in hue, and others followed suit ; but the original 
epithet was probably a copyist's mistake. It is at 
all events not to be depended on. 

Secondly, as to the distance of Sirius. 

Like a few other stars, Sirius lies not quite so 
far away as to be beyond reach of measurement. 



Some Particular Suns. 271 

No base-line upon earth would cause the slightest 
seeming change of position in him, but as our 
earth journeys round the sun the line from one 
side of her orbit to the other is found wide 
enough. A base-line of one hundred and eighty- 
five millions of miles does cause just a tiny seem- 
ing change. 

It is very little even with Alpha Centauri, and 
with Sirius it is much less. The " displacement " 
of Sirius is so slight that to measure his distance 
with exactness is impossible. Roughly calculated, 
Sirius lies at a distance of about fifty billions of 
miles. Our sun, at the distance of Sirius, would 
shine merely as a star of the third magnitude. 
Light, which reaches us from the sun in nearly 
nine minutes, and from Alpha Centauri in four 
years and one-third, cannot reach us from Sirius 
in much less than twenty years. 

Thirdly, as to the size of Sirius. 

Here, of course, we are in difficulties. Ra- 
diantly as Sirius shines on a clear night, and daz- 
zling as he looks through a powerful telescope, he 
shows no real disc or round surface capable of 
being measured. But although we cannot meas- 
ure his siza we do know something of his weight 
and of his extraordinary brilliance. The bright- 



272 Sun, Moon, and Stars. 

ness of Sirius is so much greater than the bright- 
ness of our sun would be at that same distance 
that it certainly seems to point to the fact of 
Sirius being very much the larger sun of the 
two. 

The only reliable method by which a star's 
probable weight can be calculated is through the 
discovery of a companion to the star and a knowl- 
edge of their relative distances, their times of 
revolution, and the speed of either. For a long 
while, since Sirius was not known to possess a 
companion, this mode of computation could not 
be followed. 

Like other suns Sirius has his " proper mo- 
tion, " as it is called — an outward whirl through 
space of more than one thousand miles each 
minute: sometimes more, sometimes less. Mys- 
terious irregularities in the pace of Sirius were 
noted as long ago as the year 1844, and by dint 
of careful thought a decision was reached that 
some large disturbing orb must surely belong 
to Sirius and revolve round him, a body large 
enough and near enough to exercise a disturbing 
influence over the great sun, now hastening him 
on, now pulling him back, even as Jupiter and 
Saturn by turns hurry and delay one another. 



Some Particular Suns. 273 

There the matter rested during fully eighteen 
years. Then one night the dim gleam of this com- 
panion was actually seen ; and having been once 
discovered, it was perceived again and again. So 
the truth of the surmise reached nearly twenty 
years earlier through simple exercise of reasoning 
power was proved beyond question. 

Although this faintly -shining second star is so 
near to Sirius as greatly to affect the movements of 
the latter, disturbing his regularity of speed to an 
extent which could be noted forty billions of miles 
away — yet the distance between Sirius and his 
companion is somewhere about thirty-seven times 
as great as our earth's distance from the sun. 
The dim companion appears to be in weight 
about equal to our sun, while the bright star, 
Sirius, is not much more than twice as heavy. 

Weight, however, tells little as to size. The 
blazing radiance of Sirius is extraordinary com- 
pared with the dimness of his companion sun. 
Probably the latter is far cooler and consequently 
far denser and smaller in make : while the daz- 
zling Sirius has doubtless a photosphere of incan- 
descent gases and glowing molten clouds, like 
to that of our sun, but greatly exceeding it either 
in size or in actual brilliance, or probably in both. 

Sun, Moon, etc. 1 3 



2 74 Sun, Moon, and Stars. 

Fourthly, as to the motions of Sirius, already 
touched upon. 

It was long possible only to observe the move- 
ments of a star when he journeyed sideways across 
the sky. A star coming directly towards us or 
passing straight away from us would always ap- 
pear to be at rest. Now, however, by means of 
the spectroscope it has become possible to per- 
ceive and measure the "end on " motions of stars 
to and from our Solar System as well as their side- 
way journey ings. 

The sideway motion of Sirius had been dis- 
covered before, but it now appears that he does 
not move exactly sideways. He rushes away in a 
slanting direction at the rate of over one thousand 
millions of miles each year. Think how many 
millions upon millions of millions of miles he 
must now be farther off from us than in the 
years of the ancients! Yet he shines on with 
undimmed radiance, still the most brilliant star in 
our sky — so small a matter are all those mil- 
lions compared with the sum of his vast distance 
from earth ! 

It is an interesting fact that while Sirius is 
moving away from us, we are also moving away 
from him. Our " first station ahead," which seems 



Some Particular Suns. 275 

to lie in or near the constellation of Hercules, 
stands just in the opposite direction from the goal 
of Sirius. 

Fifthly, has Sirius a family or a system of 
worlds like our sun ? 

He may have, or he may not. One companion 
he does possess, in the shape of a companion sun, 
greatly inferior to himself in lustre. Whether 
those two suns possess a family of revolving 
worlds we have no power to say. If one asks, 
Why not ? no reason to the contrary can be given. 
But to say that a thing may be is not to say that 
it is. Any star in the heavens may have such a 
family, and any star may pursue his lonely path 
without an attendant near. 

When we do not and cannot know, it is worse 
than useless to be positive. Still, the discovery 
after long ages of this dim huge companion to 
Sirius, and the knowledge that a very slight fur- 
ther increase of dimness, or decrease, rather, of 
shining, would have made that companion abso- 
lutely undiscoverable by us, is full of significance. 
Even a faint star at that distance can barely be 
detected ; and a planet, shining by borrowed light, 
could not possibly become visible. Such bodies 
may exist in countless billions throughout space 



276 Sun, Moon, and Stars. 

where we see only the glimmer of a more radiant 
sun dotting here and there the vast expanse. The 
mere possibilities thus opened out to imagination 
are almost appalling ! 

Lastly, what is Sirius made of ? 

Here again the spectroscope comes to our aid. 
Before the discovery of Spectrum -Analysis, and 
its application to astronomy, astronomers can 
scarcely be said to have known with certainty 
that stars were suns ; and of the composition of 
those stars, nay, even of our own sun, they were 
in ignorance. 

Now we have learned much ! Now the spec- 
troscope, by breaking up and analyzing the slen- 
der ray of light which travels earthward from 
each star, has shown us something of the true 
nature of those far-off lamps of heaven. Now we 
know that most of the stars — not all of them — 
are, like our sun, " great radiating machines " for 
the giving forth of light and heat and power. 
Like our sun each is surrounded by a brilliant pho- 
tosphere, formed in a fiery atmosphere of heated 
and glowing gases. 

In the White Suns, of which Sirius is king and 
chief, while sodium, magnesium, and other metals 
do more or less exist, the principal component of 



Some Particular Suns. 277 

this dazzling envelope is found to be incandescent 
hydrogen. 

Our sun belongs, not to the first or Sirian 
Class of White Suns, but to the second or Solar 
type of Golden Suns. In them, though hydrogen 
is abundant, it is not so absolutely prominent. 



278 Sun, Moon, and Stars, 



CHAPTER III. 

DIFFERENT KINDS OF SUNS. 

" Great things doeth He, which we cannot comprehend." — 
Job 37 : 5. 

Various in kind, various in size, various in 
color, various in position, various in motion, are 
the myriad suns scattered through space. 

So far are they from being formed on the same 
plan, turned out on the same model, that it may 
with reason be doubted whether any two stars 
could be found exactly alike. Why should we 
expect to find them so? No two oak-leaves, no 
two elm-leaves, precisely alike are to be found 
upon earth. 

So some stars are large, some are small. Some 
are rapid in movement, some are slow. Some are 
yellow, some white, some red, green, blue, purple, 
or gray. Some are single stars ; others are ar- 
ranged in pairs, trios, quartettes, or groups. Some 
appear only for a time, and then disappear alto- 
gether. Others are changeful, with a light that 
regularly waxes and wanes in brightness. 



Different Kinds of Suns. 279 

We have now to give a little time and thought 
to Variable Stars and Temporary Stars; after- 
wards to Double Stars and Colored Stars. 

There are many stars which pass through 
gradual and steady changes, first brightening, 
then lessening in light, then brightening again. 

One such star is to be seen in the constellation 
of the Whale. It is named " Mira," or the " Mar- 
vellous/' and the time in which its changes take 
place extends to eleven months. For about one 
fortnight it is a star of the second magnitude. 
Through three months it grows slowly more and 
more dim, till it becomes invisible not only to the 
naked eye, but through ordinary telescopes. 
About five months it remains thus. Then again 
during three months it grows brighter and 
brighter, until it is once more a second -magni- 
tude star, and after a fortnight's pause begins 
anew to fade. 

There is also a variable star in the constella- 
tion of Perseus named Algol. This too waxes 
and wanes regularly, but much more rapidly, 
since it runs through its list of changes in less 
than three days. It never becomes brighter than 
a star of the second magnitude or dimmer than a 
star of the fourth magnitude. 



280 Sun, Moon, and Stars. 

Another variable star, Betelgeuse, in Orion, 
undergoes its variations in about two hundred 
days ; while yet another, Delta Cephei, takes only 
six days. 

Our own sun has been reckoned as in some 
slight degree a variable star, passing through his 
changes in eleven years. When the sun-spots are 
most numerous he might appear, possibly, if seen 
from a great distance, slightly more dim than 
when there are none of them. 

Sometimes a new or Temporary Star appears, 
blazing brightly for a brief space and then van- 
ishing. It may be a dim star, already known, 
which thus springs into a new and radiant phase 
of being; or it may be, practically to us, a new 
existence. But doubtless the star was there be- 
fore, a body too faint for us to perceive; and 
doubtless it is there still when the fires of its out- 
burst die away, once more too faint for its shining 
to reach our eyes. 

An extraordinary specimen of a temporary 
star was seen in 1572. It was not a comet, for it 
had no coma or tail, and it never moved from its 
place. The brightness of the star was so great as 
to surpass Sirius and Jupiter and to equal Venus 



Different Kinds of Suns. 281 

at her greatest brilliancy. Nay, it must have sur- 
passed even Venus, for it was plainly visible at 
mid-day in a clear sky. Gradually the light faded 
and grew more dim, till it became a mere faint 
star. As it lessened in brilliancy it also changed 
in color, passing from white to yellow and from 
yellow to red. This succession agrees with the 
three tints of the first, second, and fourth orders 
of suns as lately classified. 

Many other instances have been known, be- 
side those referred to, of variable and temporary 
stars. 

There are two distinct kinds of double-stars. 
First we have those which merely seem to be 
double, because one lies almost directly behind 
the other, though widely distant from it — just as a 
church-tower two miles off may appear to stand 
close side by side with another church-tower two- 
and a half miles off, though they are in fact sepa- 
rated. Secondly, we have the real systems of two 
suns belonging to one another, the smaller mov- 
ing round the larger, or more correctly both trav- 
elling round one central point called the centre of 
gravity, the smaller having the quicker rate of 
motion. 



282 Sun, Moon, and Stars. 

Alpha Centauri and 61 Cygni have been 
already described as examples of true double- 
stars. 

In the constellation Lyrae a marked instance is 
to be seen. The brightest star in the Lyre is 
Vega, and near Vega shines a tiny star which to 
people with particularly clear sight has some- 
times rather a longish look. 

If you examine this star through an opera- 
glass, you will find it to consist of two separate 
stars. 

But if you get a more powerful telescope and 
look again, you will find that each star of the 
couple actually consists of two stars. The four 
are not at equal distances. Two points of light 
seemingly close together are parted by a wide 
gap from two other points equally close together. 
These four stars are believed to have a double 
motion. Each of the separate pairs revolves by 
itself, the two suns travelling round one centre ; 
and in addition to this the two couples of suns 
probably perform a long journey round another 
centre common to them all. 

Many thousands of double stars have been dis- 
covered; and a large number of these are now 
known to be not merely two distinct suns lying 



Different Kinds of Suns. 283 

in the same line of sight, but two brother-suns, 
each probably the centre of his own system of 
planets. 

We have not only to consider the number of 
suns, though of simple numbers more yet remains 
to be said : attention must also be given to the 
varying colors of different stars. 

For all suns in the universe are not made after 
the model of our sun. All suns are not yellow. 

So far as single stars are concerned, colors 
seem rather limited. White stars, golden or 
orange stars, ruby -red stars, placed alone, are 
often seen ; but blue stars, green stars, gray stars, 
silver stars, purple stars, are seldom if ever visible 
to the naked eye or known to exist as single stars. 

Take a powerful telescope and examine star- 
couples, and a very different result you will find. 
Not white, yellow, and red alone, but blue, pur- 
pie, gray, green, fawn, buff, silvery white, and 
coppery hues will delight you in turn. 

As a rule, when the two stars of a couple are 
alike in color they are either white or yellow or 
red. Also in the case of double stars of different 
colors, the larger of the two is almost invariably 
white or some shade of yellow or red. 



284 Sun, Moon, and Stars. 

There are, however, exceptions to all such 
rules. Blue stars are almost never seen alone, 
and as one of a pair the blue star is generally, if 
not invariably, the smaller. But instances are 
known of double-stars both of which are blue ; 
and one group in the southern heavens is entirely 
made up of a multitude of bluish suns. 

It is when we come to consider double-stars of 
two colors that the most striking effects are 
found. 

Now and then the two suns are nearly the 
same in size, but more commonly one is a good 
deal larger than the other. This is known by 
the brighter light of the larger and the more 
rapid movements of the smaller. The lesser 
star is often only small by comparison, and may 
be in reality a very goodly and brilliant sun. 

Among nearly six hundred "doubles" exam- 
ined by one astronomer there were three hundred 
and seventy-five in which the two stars were of 
one color, generally white, yellow, orange, or red. 
The rest were different in tint — the difference 
between the two suns in about one hundred and 
twenty cases being very marked. 

For instance, a red "primary," as the larger 
star is called, will be seen with a small green satel- 



Different Kinds of Suns. 285 

lite ; or a white primary will have a little brother- 
sun of purple or of dark ruby or of light red. 
Sometimes the larger sun is orange, the com- 
panion being purple or dark blue. Again, the 
chief star will be red with a blue satellite, or yel- 
low with a green satellite, or orange with an 
emerald satellite, or golden with a reddish-green 
satellite. We hear of golden and lilac couples, of 
cream and violet pairs, of white and green com- 
panions. But indeed the variety is almost endless. 

There may be worlds circling round these 
suns — worlds perhaps with living creatures on 
them. We know little about how such systems 
of suns and worlds may be arranged. Probably 
each sun would have his own set of planets, and 
both suns with their planets would travel round 
one central point. Perhaps, where the second 
sun is much the smallest, it might occasionally be 
like a big blazing satellite among the planets. 

Among colored stars, single and double, a few 
may be mentioned by name as examples. 

Sirius, as already observed, is a brilliant white 
sun ; and brilliant white also are Vega, Canopus, 
Regulus, Spica, and many others. 

Capella, Procyon, the Pole-star, and our own 
sun are examples of yellow stars. 



286 Sun, Moon, and Stars. 

Aldebaran, Betelgeuse, and Pollux are ruby- 
red. 

Antares is a red star with a greenish " scintilla- 
tion " or change of hue in its twinkling. A tiny- 
green sun belonging to this great and brilliant 
red sun has been discovered. Antares is some- 
times called " the Sirius of Red Suns." 

The two double-stars, 61 Cygni and Alpha 
Centauri, are formed each of two orange suns. 

In the Southern Cross there is a wonderful 
group of stars, consisting of about one hundred 
and ten suns, nearly all invisible to the naked 
eye. Among the principal stars of this group, 
which Sir John Herschel described as being, 
when viewed through a powerful telescope, like 
"a casket of variously colored precious stones," 
are two red stars, two bright green, three pale 
green, and one of a greenish-blue. 



Groups and Clusters of Suns. 287 



CHAPTER IV. 

GROUPS AND CLUSTERS OF SUNS. 

" He telle th the number of the stars ; He calleth them all by 
their names." — Psa. 147 14. 

We have been thinking a good deal about 
single stars and double stars as seen from earth. 
Now we have to turn our attention to groups, 
clusters, masses of stars in the far regions of 
space. 

Have you ever noticed on a winter night, 
when the sky was clear and dotted with twinkling 
stars, a band of faintly -glimmering light stretch- 
ing across the heavens from one horizon to 
the other ? 

The band is irregular in shape, sometimes 
broader, sometimes narrower, here more bright, 
there more dim. If you were in the southern 
hemisphere you would see the same soft belt of 
light passing all across the southern heavens. 
This band or belt is called the Milky Way. 
Sometimes it is called "the Stellar System," or 



288 Sun, Moon, and Stars. 

"the Universe." Early in this book mention was 
made of the word "universe" as used in two 
senses. The more modern use of it for the 
Milky Way, or for the particular great galaxy or 
gathering of stars to which our sun belongs, is 
the smaller meaning. 

But what is the Milky Way ? 

It is made up of stars. So much we know. As 
the astronomer turns his telescope to the zone of 
faintly-gleaming light he finds stars appearing 
behind stars in countless multitudes ; and the 
stronger his telescope, the more the white light 
changes into distant stars. 

Our sun we believe to be one of the stars of the 
Milky Way, merely one star among millions of 
stars, merely one golden grain among the millions 
of sparkling gold-dust grains scattered lavishly 
through creation — scattered not recklessly, not by 
chance, but placed, arranged, and guided each by 
its Maker's upholding hand. 

The Milky Way, the Galaxy, or the Universe, 
as it has been variously called, has great interest 
for astronomers. Many have been the attempts 
made to discover its actual size, its true shape, 
how many stars it contains, how far it extends. 
But to all such questions the only safe answers to 



Groups and Clusters of Suns. 289 

be returned are fenced around with "perhaps" 
and "may be," 

There are many very remarkable clusters of 
stars to be seen in the heavens — some few visible 
as faint spots of light to the naked eye, though 
the greater number are only to be seen through a 
telescope. Either with the naked eye or in tele- 
scopes of varying power they show first as mere 
glimmers of light, which, viewed with a more 
powerful telescope, separate into clusters of distant 
stars. 

The most common shape of these clusters is 
globular — to the eye appearing simply round. 
Stars gather densely near the centre and gradually 
open out to a thin scattering about the edge. 
Thousands of suns are often thus collected into 
one cluster. 

The clusters are to be seen in all parts of the 
sky, but the greater number seem to be gathered 
into the space covered by the Milky Way and by 
the famous south Magellanic Clouds. 

Some of them are beautifully colored, as, for 
instance, a cluster in Toucan, not visible from 
England, the centre of which is rose-colored, bor- 
dered with white. No doubt it contains a large 

Sun, Moon., etc. IQ 



290 Sun, Moon, and Stars. 

number of bright red suns surrounded by a scat- 
tering of white suns. 

By some it is supposed that many of these 
clusters may be other vast galaxies of stars, more 
or less like the Milky Way, lying at enormous dis- 
tances from us. 

Others, on the contrary, rather maintain that 
such clusters, instead of being separate " uni- 
verses" from our own, are merely lesser star- 
systems, included within our great Stellar System, 
and probably all travelling round some one centre. 

For the present this must be considered an 
open question. But in either case if worlds are 
journeying among the suns of such a starry clus- 
ter, what sights might not be witnessed by their — 
possible — inhabitants ! 

We do not indeed know the distances between 
the separate suns of a cluster, which may be far 
greater than appears to us. Yet, on the other 
hand, it may well be that they are near enough 
together to shed bright light on all sides of a 
planet revolving in their midst. The planet might 
or might not have within view a single sun equal 
in apparent size to our sun as seen from earth ; 
yet thousands of lesser suns shining night and 
day would cause a radiance which we never enjoy. 



Groups and Clusters of Suns. 291 

No, not night. In such a world there could be 
no night. Worlds in the midst of a star-cluster 
must be regions of perpetual day. No night, no 
starry heaven, no sunrise lights or sunset glories, 
no shadow mingling with sunshine, but one con- 
tinual ceaseless blaze of brightness. We can 
hardly picture even in imagination such a condi- 
tion of things. 

Beside star-clusters there are also Nebulae. 

The word " nebula" comes from the Latin 
word for " cloud/' and the nebulae are so named 
from their hazy and cloud-like appearance. 

It is not always easy at first sight to distinguish 
between nebulae and very distant star - clusters. 
Both have the same dim and cloudy look. In 
days gone by the star-clusters were often included 
by astronomers under the general term of nebu- 
lae. And as with star-clusters, so with many neb- 
ulae, more powerful telescopes have shown them 
to be great systems or collections of innumerable 
stars crowded together by vastness of distance. 

But although some nebulae are really, to a cer- 
tain extent, much the same as star-clusters, others 
are entirely different. The spectroscope, by its 
delicate test, proves them to consist of enormous 



292 Sun, Moon, and Stars. 

masses of glowing gas, and not to be solid bodies 
at all, even in the limited sense in which we may 
call our sun a " solid " body. Whether they are 
on their road to become solid bodies by-and-by, is 
another question. Certainly they are not so yet. 

By glowing gas I do not mean burning gas, like 
the gas alight at a chandelier burner. For actual 
burning — for being consumed and wasting away — 
an atmosphere such as ours is necessary. The 
gases which compose the outer envelopes of sun 
and stars, and the gases which compose the whole 
body of many a nebula, shine with intensity of 
glowing but non-consuming heat ; and this is 
termed incandescence. 

The number of nebulae now known amounts to 
thousands. They are usually divided into classes, 
according to their apparent shapes, as seen from 
earth. There are circular nebulae, oval nebulae, 
annular nebulae, conical nebulae, cometary nebulae, 
spiral nebulae, and nebulae of divers other descrip- 
tions. These apparent shapes would doubtless 
change greatly if we could look upon them from 
some other standpoint and at a lessened distance. 
Even when seen in more powerful telescopes, they 
often wear a totally different aspect. 

Many nebulae are believed to lie at incalculable 



Groups and Clusters of Suns. 293 

distances : and the light which comes to us from 
them may have been hundreds of years tipon its 
road. But opinions differ much on this question. 
Some astronomers place many of the nebulae, as a 
matter of probability, far outside the vast Stellar 
System to which we belong ; while others believe 
that most if not all of the gaseous nebulae are in- 
cluded within the bounds of our own particular 
starry universe. 

Mention must be made of the great nebula in 
Orion. The middle star of Orion's sword-handle, 
when carefully noted with the naked eye, can be 
seen to have a slightly misty aspect. This, seen 
in powerful telescopes, develops into a glorious 
nebula, one of the grandest in our heavens. It is 
shown by the spectroscope to consist partly of 
stars, partly of glowing gas — of cotftitless suns, 
possibly not large in size, but great in numbers, 
" bathed in and surrounded by a wStupendous mass 
of glowing gas !"* — hydrogen gas, nitrogen gas, 
and one other gas, the nature of which we do not 
know. 

As for the size of this nebula, we are driven 
to conjecture ; but undoubtedly it is enormous. 
Measurement of size is impossible where measure- 
* R. S. Ball. 



294 Sun, Moon, and Stars. 

ment of distance cannot be accomplished. It has, 
however, been suggested that, if a ball be imag- 
ined so huge as to fill the entire circle of our 
earth's annual pathway round the sun, one million 
of such vast globes of light might be less in size 
than the nebula in Orion. How much larger yet 
it may be none can venture to say. 

Another famous nebula is that in Andromeda. 
It can be seen by the naked eye and has been 
sometimes taken for a comet. The spectroscope 
shows this nebula to be formed seemingly, not of 
glowing gas, but of multitudinous faint stars : so 
it is more akin to an ordinary star-cluster. 

Before quitting this subject allusion should be 
made to the famous Magellanic Clouds in the 
southern heavens. Sometimes they are called the 
Cape Clouds. 

They differ from other nebulae in many points, 
and more particularly in their apparent size. The 
Great Cloud is about two hundred times the size 
of the full moon, while the Small Cloud is about 
one quarter as large. In appearance they are not 
unlike two patches of the Milky Way, separated 
and moved to a distance from the main stream. 

These clouds are surrounded by a very barren 
portion of the heavens, containing few stars ; but 



Groups and Clusters of Suns. 295 

in themselves they are peculiarly rich. Seen 
through a powerful telescope they are found to 
abound with stars. The Greater Cloud alone con- 
tains over six hundred from the seventh to the 
tenth magnitudes, countless tiny star-points of 
lesser magnitudes, star-clusters of all descriptions, 
and nearly three hundred nebulae — all crowded 
into this seemingly limited space. 



296 Sun, Moon, and Stars. 



CHAPTER V. 



THE MILKY WAY. 



" Who knoweth not in all these that the hand of the Lord 
hath wrought this ?" — Job 12:9. 

"One star differeth from another star in glory." — 1 Cor. 
15:41. 

The Milky Way forms a soft band of light 
round the whole heavens. In the southern hemi- 
sphere as in the northern hemisphere it is to 
be seen. 

In some parts the band narrows, in some parts 
it widens. Here it divides into two branches. 
There we find dark spaces in its midst. One such 
space in the south is to the naked eye so black 
and almost starless as to have been named the 
Coal-sack. But photography shows abundance of 
stars to lie there also. 

All along, over the background of soft dim 
light, lies a scattering of brighter stars shining on 
its surface. 

Much interest and curiosity have long been 
felt about this mysterious Milky Way. That it 
consists of innumerable suns, and that our sun is 



The Milky Way. 297 

one among them, has been believed for a consid- 
erable time. But other questions arise. How- 
many stars does the Milky Way contain ? What 
is its shape ? How far does it reach ? 

No harm in asking the questions, only we have 
to be satisfied in astronomy to ask many questions 
which cannot yet receive answers. No harm for 
man to learn that the utmost reach of his intellect 
must fall short in any attempt to sound the depths 
of the universe — even as the arm of a child would 
fall short in seeking to sound the depths of the 
ocean over the side of a little boat. 

For attempts have been made to sound the 
depths of our star-galaxy out of this little earth- 
boat. 

The idea first occurred to the great Herschel, 
and a grand idea it was — only a hopeless one. 

He turned his powerful telescope north, south, 
east, west. He counted the stars visible at one 
time in this, in that, in the other directions. He 
found a marked difference in the numbers. The 
portion of sky seen through his telescope was 
about one quarter the size of that covered by the 
moon. Sometimes he could merely perceive two 
or three bright points on a black background, at 
other times the field of his telescope was crowded. 



298 Sun, Moon, and Stars, 

In the fuller portions of the Milky Way he had 
four or five hundred stars under view at once. In 
one place he saw about one hundred and sixteen 
thousand stars pass before him in a single quarter 
of an hour. 

Herschel took it for granted that the stars of 
the Milky Way, uncountable in numbers, are as a 
rule much the same in size ; so that brightest stars 
would as a rule be nearest, and dimmest stars 
would as a rule be farthest off. Where he found 
stars clustering thickly, beyond his power to pene- 
trate, he believed that the Milky Way reached 
very far in that direction. Where he found black 
space, unlighted by stars or lighted by few stars, 
he decided that he had found the borders of our 
galaxy in that direction. 

Following these rules which he had laid down, 
he made a sort of rough sketch of what he sup- 
posed might be the shape of the Milky Way. He 
thought it was somewhat flat, extending to a good 
distance breadthways and a much greater distance 
lengthways, and he placed our sun not far from 
the middle. This imagined shape of the Milky 
Way is called " the Cloven-Disc Theory." To 
explain the appearance of the Milky Way in the 
sky Herschel supposed it to be cloven or split 



The Milky Way. 299 



through half of its length, with a black space 
between the two split parts. 

It seems that Herschel did not hold strongly 
to this idea in later years, and the rules on which 
he formed it no longer hold good. 

For how do we know that the stars of the Milky 
Way are as a rule much the same in size ? Cer- 
tainly the planets of the Solar System are very 
far from being uniform ; and the few stars whose 
weight can with any certainty be measured seem 
to vary considerably. There is a great difference 
also between the large and small suns in many of 
the double stars. 

Again, although bright stars undoubtedly are 
as a rule the nearest and dim stars farthest off, 
there are many exceptions. Look at Sirius and 61 
Cygni — Sirius, the most radiant star in the heav- 
ens, and 61 Cygni, almost invisible to the naked 
eye. According to this rule, 61 Cygni ought to 
lie at an enormous distance beyond Sirius. Yet 
in actual fact Sirius is the farther away of the 
two. 

For aught we know there may be many small 
telescopic stars much nearer to us than many of 
the brighter stars which we can plainly see with 
the naked eye, and only invisible without the help 



300 Sun, Moon, and Stars, 

of the telescope because of their smallness, not so 
much because of their distance. 

This line of reasoning shows how easily mis- 
takes may have been made in a matter of no slight 
importance. Some chapters back I spoke of the 
light travelling to us from far-distant stars — stars 
so distant that their light must have taken thou- 
sands of years to reach us. 

Only there is no must. We do not actually 
know the fact. A writer says: "The illustrious 
Herschel penetrated on one occasion into this 
spot " — the star-cluster on the sword-hand in the 
constellation of Perseus — " until he found himself 
among depths whose light could not have reached 
him in less than four thousand years." 

So Herschel believed, but he did not know. 
There is no certain " could not " in the matter. 
The distance of those stars had not and has not 
been mathematically measured. Herschel judged 
of it by their dimness, by the strong power needed 

to make them visible, and by the rules which he 

« 

had adopted as most likely true. 

This was no sure mode of judging. The 
stars might be as far distant as he supposed. On 
the other hand they might be very much nearer. 
If too far for our measuring-line to reach them, 



The Milky Way. 301 

they may be only just too far ; and their seeming 
smallness and dimness, instead of being caused 
by vast reaches of space between, may simply be 
caused by actual smallness or actual dimness. 
There are little suns as well as great suns in the 
Milky Way. It is possible that hundreds of little 
suns may exist for every single specimen of a great 
sun. 

Again, when Herschel found black spaces in 
the heavens, almost void of stars, and believed 
that he had reached the outside borders of the 
Milky Way, he might be right or he might be 
mistaken. The limit might lie there, or thou- 
sands more of small stars might extend in that 
very direction too far off for their little glimmer 
to be seen through the most powerful telescope. 

A good deal of attention has been paid to the 
arrangement of stars in the sky. The more the 
matter is looked into the more it appears that 
stars are neither regular in size nor regular in dis- 
tribution. It would seem that they are not flung 
broadcast through the heavens, each one alone 
and independent of the rest. They are placed 
often, as we have already seen, in pairs, in triplets, 
in quartettes, in clusters. Also the great masses 



302 Sun, Moon, and Stars. 

of them in the heavens seem to be more or less 
arranged in streams and sprays and spirals. It 
should, however, be understood that what may 
look to us like streams or spirals may in reality be 
nothing of the kind. Distance is very deceptive. 
Even on earth any object far off may appear to be 
close to another object from which it is really 
separated by many miles ; and if this is so on our 
little earth, how much more easily may one be 
mistaken in celestial landscapes. 

We must now try to form a few clear ideas 
about the richer and poorer parts of the heavens 
as viewed from earth. 

In considering stars of the first six magnitudes 
only — stars visible to the naked eye — a somewhat 
larger number is found in the southern hem- 
isphere than in the northern hemisphere. In 
both hemispheres there are regions densely 
crowded with stars and regions by comparison 
almost empty. 

It has been long questioned whether the num- 
ber of bright stars is or is not greater in the Milky 
Way than in other parts of the sky. 

Careful calculations have at length been made. 
It appears that the whole of the Milky Way — that 
zone of soft light passing round the earth — covers, 



The Milky Way. 303 

if we leave out the Coal-sack and other such gaps, 
between one-tenth and one-eleventh of the whole 
heavens. 

The entire number of naked-eye stars, or stars 
of the first six magnitudes, does not exceed six 
thousand, and of these, eleven hundred and fif- 
teen lie scattered along the bed of the Milky Way 
stream. 

If the brighter stars were scattered over all 
the sky as thickly as throughout the Milky Way, 
their number would amount to twelve thousand 
instead of only six thousand. This shows us that 
the higher magnitude stars really are collected 
along the Milky Way in greater numbers than 
elsewhere. 

In the dark spaces of the Milky Way, on the 
contrary, bright stars are so few that if they were 
scattered in the same manner over all the sky, 
their present number of six thousand would come 
down to twelve hundred and forty — which would 
be a serious loss. 

No rest, no quiet, no repose in that great uni- 
verse which to our dim eyesight looks so fixed 
and still, but one perpetual rush of moving suns 
and worlds. 



304 Sun, Moon, and Stars. 

For every star has its own particular friotion ; 
every sun is pressing forward in its own appointed 
path. 

And among the myriads of stars — bright 
blazing spheres of white or golden, red, blue, or 
green radiance, sweeping with steady rush through 
space, our sun also hastens onward. 

When I speak of the sun's movement, it must 
of course be understood that the earth and planets 
all travel with him, much as a great steamer on 
the sea might drag in his wake a number of little 
boats. From one of the little boats you could 
judge of the steamer's motion quite as well as if 
you were on the steamer itself. Astronomers 
judge partly of the sun's motion by watching the 
seeming backward drift of stars to the right and 
left of him ; and the watching can be as well ac- 
complished from earth as from the sun himself. 

After all, this mode of judging is and must be 
very uncertain. Among the millions of stars 
visible we know the distances, roughly, of less 
than one hundred ; and every star has its own real 
motion, which has to be separated from the ap- 
parent change of position caused by the sun's 
advance. 

It seems now probable that the sun's course is 



The Milky Way. 305 

directed more or less towards the neighborhood 
of the constellation Hercules. But if orbits of 
suns, like orbits of planets, are ellipses, he will 
curve away sideways long before he reaches Her- 
cules. 

Another investigation gives the neighborhood 
of 61 Cygni as our " next station." 

It is difficult to give any clear idea of the im- 
mensity of the universe — even of that portion of 
the universe which lies within reach of our most 
powerful telescopes. How far beyond such limits 
it may reach we lose ourselves in imagining. 

Earlier in the book we have supposed possible 
models of the Solar System, bringing down sun 
and worlds to a small size, yet keeping due pro- 
portions. What if we were to attempt to make a 
reduced model of the universe — that is, of just so 
much of it as comes within our ken ? 

Suppose a man were to set himself to form 
such a model, including every star which has 
ever been seen. 

Let him have one tiny ball for the sun and 
another tiny ball for Alpha Centauri, and let him as 
a beginning set the two one yard apart. That sin- 
gle yard represents ninety-one millions oif miles 
20 



306 Sun, Moon, and Stars. 

two hundred and thirty thousand times repeated. 
Then let him arrange countless multitudes of 
other tiny balls at due distances — some five times, 
ten times, twenty times, fifty times as far away 
from the sun as Alpha Centauri. 

It is said that the known universe, made upon 
a model of these proportions, would be many 
miles in length and breadth. 

But the model would appear fixed as marble. 
The sizes and distances of the stars being so 
enormously reduced, their rates of motion would 
be lessened in proportion. Long intervals of 
time would need to pass before the faintest motion 
in one of the millions of tiny balls could become 
visible to a human eye. 



Reading the Light. 307 



CHAPTER VI. 

READING THE LIGHT. 

" God said, Let there be light; and there was light." Gen. 
1:3. 

Many times in the course of this little book 
mention has been made of an instrument called 
the Spectroscope, to which much of our present 
knowledge of the heavens is due. The subject 
of Spectrum Analysis is too complex to be fully 
discussed in a volume of this kind ; but a few 
words of explanation may be desirable. 

By means of the spectroscope we know, with 
almost certainty, many of the substances which 
are contained in the sun, in the stars, in nebulae- 
How large, or how far away, or how quickly mov- 
ing, some of the heavenly bodies are, could be 
discovered through the telescope without help 
from the spectroscope ; but the actual make of 
them lay, until recent years, beyond our grasp. 

Not upon earth alone, but also in the sun, 
exist iron and sodium, copper and zinc, magnesium, 
cobalt, and many other substances with which we 
are familiar — notably, hydrogen. 



308 Sun, Moon, and Stars. 

Every metal may be either in the solid or in 
the liquid or in the vapor form. Iron, as we 
commonly see it, is solid ; in other words, it is 
frozen, like ice. Most metals freeze at a much 
lower temperature than water does. Just as a cer- 
tain increase of heat will turn ice into water, so 
a certain increase of heat will transform solid iron 
into liquid iron. And just as yet greater heat 
will turn water into steam, so very much greater 
heat will transform liquid iron into vapor of iron, 
or iron gas. A little heat will do for ice what im- 
mense heat will do for iron. 

The intense heat of the sun causes metals 
which are solid upon earth to float as glowing 
vapor in the solar atmosphere. Indeed, that 
dense and far-reaching atmosphere is largely 
composed of such metals. Whether iron and 
other earthly metals can be found anywhere in or 
near the sun in anything approaching to a solid 
form is more than doubtful; but in the photo- 
sphere they probably do exist in a shape border- 
ing on the liquid form, where glowing clouds ap- 
pear to float, formed of condensed and radiant 
metals. This state would answer, not to the liquid 
waters of a river, but to the condensed water- 
droplets of a fog or cloud. 



Reading the Light. 309 

Spectrum Analysis, beside teaching us what 
metals may be found in the sun, has also a word 
to say about those which exist in some of the 
stars. Far distant as those suns of light are, we 
know that in them too are such earthly materials 
as iron, sodium, magnesium, and a variety of 
kindred substances, while in many of them hydro- 
gen predominates. 

But how can we know all this ? How could 
the wildest guessing grow to more than a guess 
and reveal to us the actual presence in even our 
own particular sun of iron or hydrogen, not to 
speak of more distant suns ? 

We know it by means of Spectrum Analysis. 

The spectroscope may be looked upon as twin- 
sister to the telescope. A telescope gathers to- 
gether widely-scattered rays of light into a spot or. 
focus for our use. The spectroscope separates 
those rays of light into ribbons, sorts them, and 
enables us to read in them hidden meanings. 

When a ray of light reaches us from the sun, 
that ray is white ; but in the whiteness other hues 
are hidden. A white ray is composite in form, 
made up of many lesser rays of divers colors 
blended together. Newton was the first to dis- 
cover so much. 



3 1 o Sun, Moon, and Stars. 

If a sunlight ray is allowed to pass through a 
small round hole in the wall it will fall upon the 
opposite wall, or upon the ground, in a little round 
patch of light. 

But if a piece of glass cut into the shape of a 
prism is placed in the path of that sunbeam, the 
round patch of light vanishes. In its stead ap- 
pear several bands of soft color, each overlapping 
and melting into the next. Red, orange, yellow, 
green, blue, indigo, violet — all these become vis- 
ible. The arrangement of colors is invariably the 
same. 

Now the prism has done two things. First, it 
has bent the ray out of a straight course, causing 
it to fall in a different place from where the round 
spot lay. Secondly, it has broken up or disinte- 
grated the white ray into those differently-tinted 
rays of which it was made. And the manner of 
breaking it up is simply this — that one color is 
always more or less bent than another color, in 
passing through a prism, therefore all the different 
tints fall upon different places. 

The whole variegated band, whether of sun- 
light or of any other light, is known as the " spec- 
trum " of that light ; and the breaking up of the 
ray and searching into its make is called the "analy- 



Reading the Light, 311 

sis" of it. Thus the reading of light — whether 
earthly light, moonlight, sunlight, or starlight — 
is included under the head of Spectrum Analysis. 

At the so-called " lowest " end of the spectrum 
lies red, the least bent of all the colored rays. At 
the so-called " highest " end lies violet, the most 
bent. All other hues visible to our eyes are 
placed between. Light beyond the violet and be- 
low the red we cannot see. That is by no means 
to say that it does not exist. We can feel the 
warmth of rays below the red, although we cannot 
see them ; and photographs are taken by means of 
rays beyond both the red and violet, albeit they 
are to us invisible. By means of those faint rays 
photographs can actually be taken of countless 
stars which no living man can see through the 
most powerful telescopes. For the rays are there, 
however faint, and they will slowly impress their 
image upon prepared sensitive paper long exposed 
to their dim shining, though human eyes cannot 
gaze long or steadily enough to detect them. 

Suppose now that, for the round hole in the 
wall, we substitute a very narrow slit. Then let- 
ting the sunshine again stream through, we once 
more place a prism of glass in the path of the 
ray when it has entered the slit. 



%\2 Sun, Moon, and Stars. 

Bright bands of color are perceived anew, ar- 
ranged always in the same order, from red to 
violet. But the different colors no longer overlap 
as before ; and in addition to the bright hues, a 
great many slender dark lines of gaps in the color- 
ing are to be seen. . 

These dark lines in the spectrum of sunlight 
were for a long while a great perplexity. At first 
it was thought that they might be caused by 
something in our own atmosphere ; but this no- 
tion had to be given up. It became manifest that 
the lines were somehow connected with the sun, 
not with the earth. Wherever a ray of sunlight was 
passed through a narrow slit and analyzed, there 
they were — always the same in position. More 
and more of them were found through closer ob- 
servation, but the old ones did not change. 

A ray of moonlight was found to contain ex- 
actly the same dark lines as a ray of sunlight— 
and most naturally! For a ray of moonlight 
really is nothing more or less than a ray of sun- 
light reflected from the moon. 

But in a ray of starlight the lines were found 
to be entirely different ; and this alone is enough 
to do away with the idea of the lines being due to 
something in our air. Starlight and sunlight 



Reading the Light. 313 



both alike journey through earth's atmosphere. 
Every star has its own particular spectrum, some- 
times bands of color, like our sun's spectrum, with 
fine dark lines, only the arrangement of lines is 
never the same as those of our sun, and it is never 
the same in any two stars. 

These dark lines in sunlight and starlight tell 
us much ; and briefly, as follows : 

If the light of a white-hot metal, either solid 
or liquid, is allowed to pass through the slit and 
prism of a spectroscope, bands of bright color are 
seen, one passing into another, as with the solar 
spectrum. 

But under ordinary conditions of bodies in a 
gaseous state the spectrum does not consist of broad 
hazy bands of color, but of sharp bright lines. 

And — mark this — each particular gas has its 
own especial lines, always occupying the same 
position. A chemist knows to a certainty how 
many lines will be seen, in the case of iron gas or 
sodium gas or hydrogen gas, and where each line 
will fall. 

But suppose — mark this again — that the light 
comes either from a solid or a liquid or a highly- 
compressed gas, and passes on its way through a 
gas medium at a lower temperature, such as a 



314 Sun, Moon, and Stars. 

gas-flame or glowing gas atmosphere? In such a 
case, when the ray has gone through slit and 
prism and has spread out its spectrum of color 
bands, dark lines will be seen in those bands. 
These dark lines are gaps or breaks in the light. 
They mean the absence of part of the sunlight 
or starlight. For the gas through which that 
light has travelled on its way hitherward has 
absorbed or captured part of the light, and only 
part has been free to continue its journey. 

A ray of light from the sun's photosphere has 
to pass through the sun's atmosphere of gases ; 
and as it passes, each gas in the solar atmosphere 
takes possession of some part of it, producing 
dark lines which are peculiar to that gas. In 
consequence of this, hundreds of tiny breaks are 
formed in the solar spectrum where the much- 
robbed ray falls. 

If the light of a sodium-flame is passed through 
the spectroscope two bright lines are always seen, 
always in the same position. 

But in the sun's colored spectrum those two 
lines are dark. For the sodium in the sun's at- 
mosphere has absorbed or stolen exactly that 
part of the sunlight which would have given the 
two bright sodium lines. 



Reading the Light. 315 

The spectrum of iron means, not two, but 
hundreds of bright lines. In the solar spectrum 
these hundreds of lines are dark, because the iron 
gas in the atmosphere of the sun has absorbed all 
that part of the light-ray on its journey from the 
radiant photosphere. 

Therefore, when certain dark lines are apparent 
in the spectrum of the sun or of a star, we 
know that the metal which always shows exactly 
corresponding bright lines is present in the atmo- 
sphere of that sun or star. By the same mode 
the make of comets, of nebulae, and of other 
heavenly bodies can be tested and examined. 

This may give just a faint idea of the first 
principles of the new grand branch of Astronomy 
included under the head of Spectrum analysis. 
The science is a science of itself, however, and 
one full of complexity. Chemistry and astron- 
omy here walk hand in hand. 

The spectroscope alone can decide whether 
any particular star is in fact a sun. If the " rain- 
bow-tinted ribbon " of light is there, crossed by 
thin dark lines, due to the stellar atmosphere 
through which each ray has passed after quitting 
the photosphere, then that star may be counted a 
true sun. Such stars constitute the majority 



3 1 6 Sun, Moon, and Stars. 

among the hosts of heaven ; yet variety without 
limit is found. In one star the light from the 
photosphere is almost lost, almost absorbed by the 
surrounding atmosphere. In another, the light of 
the atmosphere so overpowers that of the photo- 
sphere that only bright gas-lines are seen in the 
spectroscope — the continuous color-band being 
comparatively faint. 

Besides telling us of the make of the stars, the 
spectroscope also speaks to us of their motions. A 
very tiny shift or movement of the little dark lines 
or bright lines, to right or left, is sufficient. From 
this can be calculated with, it is believed, astonish- 
ing exactness the rate at which a star is rushing to- 
wards us or rushing away from us. For if the star 
is nearing our earth, the light-waves coming from 
him are pressed together, so to speak, hurrying 
one upon another ; while if the star is retreating, 
the light-waves are affected in a reverse manner, 
delayed or pulled apart, if such a term may be 
used. By this method* also stars are discovered 
so dim as to be not only utterly invisible to the 
naked eye, but undiscoverable by the telescope. 

* It was Dr. Huggins who inaugurated this method of re- 
search upon the heavenly bodies, the results being communicated 
to the Royal Society in 1868. 



Further Thoughts. 317 



CHAPTER VII. 

FURTHER THOUGHTS. 

" My right hand hath spanned the heavens/' — ISA. 48 : 13. 

Early in the year 1892 a new star appeared in 
the constellation Auriga, winning much attention. 

On December 10, 1891, it made its first appear- 
ance, suddenly, as a star of the fifth magnitude. 
Two days earlier no star so bright as even the 
ninth magnitude had been visible in that part of 
the heavens. On the 20th of December it reached 
its brightest. On the 8th of February it was again 
only a star of the fifth magnitude ; and after the 
7th of March there were " remarkable swayings to 
and fro of the intensity of the light, set up proba- 
bly by commotions attendant on the cause of its 
outburst."* These lessened, and the star fell stead- 
ily to only the eleventh, and then by the 1st of 
April to the fourteenth, magnitude. At the end 
of April it was still faintly visible. 

Nova Aurigae, as this brilliant stranger has 
been named, showed under the spectroscope "a 
rainbow-tinted ribbon, in which splendid groups 
* Dr. Huggins, 



3 1 8 Sun, Moon, and Stars. 

of bright lines stood out from a paler back- 
ground ; the red ray of hydrogen, Fraunhofer's 
C, glowed . . . like a danger signal on a dark 
night ; a superb quartette of rays shone in the 
green ; shimmering blue bands and lines drew 
the eye far up towards the violet ; the character- 
istic blazing spectrum, in fact, of a new star was 
unmistakably present. The interpretation left no 
doubt that hydrogen played a large part in the 
conflagration."* 

Nor was this all that the spectroscope had to 
say! 

At the close of the last chapter brief mention 
was made of the mode in which the coming nearer 
or passing away of a star may be discovered. With 
the spectrum of Nova Aurigae an extraordinary 
thing was seen. There were distinct and unmista- 
kable signs, not of approach alone, or of a receding 
movement alone, but of both simultaneously. At 
one and the self-same moment the Nova appeared 
to be speeding away from us at a rate of two or 
three hundred miles per second and rushing to- 
wards us at much the same rate, the sum of the two 
motions together amounting to no less than about 
550 miles per second ! 

* Miss Clarke. 



Further Thoughts. 319 

At first this was explained by a conjecture that 
Nova Aurigae might consist of two stars : one of 
the two hurrying towards us and the other hurry- 
ing away from us. But the two-star explanation is 
already being given up, and astronomers are in- 
clined to think that the rush to and fro is probably 
only of heated gases on the turbulent surface of 
the star. 

For Nova Aurigae, like many or most other 
stars, is most likely a mass of intensely heated 
and glowing gases, forcibly compressed within by 
gravitation and spreading outside far away into 
a furiously-excited incandescent atmosphere. 

In any case, the history of the Nova is a re- 
markable one, and apparently we have not yet 
come to the end of it. After steadily waning to a 
very faint star, it has begun again to increase in 
brightness. What course it will follow in the fu- 
ture, time alone can show. 

Mention has been more than once made, in 
this revised edition, of the probable presence and 
absence of atmospheres on different heavenly bod- 
ies, and of apparent reasons for the same. 

An atmosphere is formed of gas-particles, or 
gas-molecules, in rapid motion. There are differ- 
ent gases, and the particles of one gas differ in 



320 Sun, Moon, and Stars. 

speed from those of another gas. Moreover, the 
colder any gas is, the more slowly its particles 
move ; the hotter any gas, the more vehemently 
its tiny molecules dash to and fro, incessantly 
striking against other molecules and striving to 
escape. 

If this is the case with our atmosphere, why 
should not all the particles of air escape in the 
course of time, passing into distant space and 
forsaking us utterly ? 

So unquestionably they would do but for the 
restraining force of gravitation. Struggle as they 
may to get away, earth's strong attraction holds 
them in leash, and they cannot flee ! 

Our atmosphere consists mainly of oxygen and 
nitrogen ; and the oxygen gas is essential for 
animal life. No free hydrogen gas floats in our 
atmosphere, although enormous quantities of it 
are present in the sun. It is very possible that 
once upon a time earth possessed hydrogen gas 
also in her air, and that she has lost it since. For 
the particles of hydrogen are exceedingly rapid in 
their motions, far more so than the particles of 
oxygen or nitrogen ; therefore they need a much 
stronger restraint to hold them in. And while 
earth is large and dense enough to keep her nitro- 



Further Thoughts. 321 

gen and oxygen gases prisoners, she has not, it 
would seem, sufficient attractive power to hold 
in hydrogen. 

If Mars has an atmosphere, or Mercury, we 
may say with tolerable confidence that no free 
hydrogen exists in it ; because neither Mars nor 
Mercury could be expected to hold fast the rap- 
idly journeying particles of hydrogen gas. It 
has even been calculated that, very probably, 
Mars is somewhere about the smallest world 
which can permanently retain an atmosphere. 

We have already seen that the moon, so far as 
we can discover, has no atmosphere. If ever the 
moon did possess one, it has doubtless all wan- 
dered away, because her attractive power was too 
weak to keep it. 

This is not merely a guess. The speed of dif- 
ferent gas particles is accurately known, and the 
strength of gravitation needed to control them is 
known also. It is no difficult matter to find out 
about how heavy a world must be to overcome by 
attraction the impetus of the busy little gas- 
molecules. But while the moon, perhaps, could 
not keep any atmosphere, and while the earth 
might be unable to hold in bondage an atmo- 
sphere of hydrogen gas, the sun has no such diffi- 

Sun, Moon, etc. 21 



322 Sun, Moon, and Stars. 

culty. His enormous bulk gives such enormous 
attractive power that the hydrogen in his atmo- 
sphere, though violently heated and furiously 
excited, is still under control. 

A most natural, though wide, step carries us 
from the restless gas - particles, breaking loose 
from control, to the larger restless heavenly 
bodies, which appear to do precisely the same 
thing. 

In our Solar System we have worlds and satel- 
lites, comets and meteors, under the sun's com- 
mand, obedient to his attractive power. We have 
also wandering comets, occasional and passing 
visitants, travelling at so rapid a pace that all the 
great attraction of the sun fails utterly to hold 
them in ; and they plunge into the depths of 
space never to return. 

In our Stellar System we have countless suns, 
double stars, clusters, and perhaps nebulae, sub- 
ject one to another, bound together by the bonds 
of mutual gravitation. But also we have, possi- 
bly, Runaway Stars, wanderers from the depths 
beyond, passing through our Starry System at a 
headlong rush which, it may be, not all the com- 
bined control of all the stars of light can check 
or hinder. If so, they doubtless will plunge into 



Further Thoughts. 323 

profounder distances, beyond the utmost stretch 
of human imagination, never to return. 

Verily, the great things and the little things 
of creation are subject to the same laws ! 

A few closing words as to the possible com- 
parative ages of different heavenly bodies may 
be of interest. 

The ages of worlds and suns cannot indeed be 
reckoned by years or by centuries. No record 
gives us the date, in past millenniums, of the birth 
of this or that bright orb. Yet, looking upon 
them from our little world, we see signs which 
seem to tell, in one of comparative youth, in an- 
other of comparative age. Nay, so marked are 
these signs, and so evidently is one stage suc- 
ceeded by another stage, that, as in looking on 
boy and man we may say with confidence that 
the one has been, or the one will be, just like the 
other, so in looking on diverse heavenly bodies 
we may conjecture that as one is another has 
been or will be. 

Positive assertions are indeed, here as else- 
where, out of place. Watching the heavens as we 
do with limited sight, and for a very brief span, 
it behooves us to be careful even in conjecture. 



324 Sun, Moon, and Stars. 

Though the marvel is that we can know so much, 
though the question may well be asked, " What 
then must the true nature of that mind be 
which thus freely associates itself with the things 
beyond the stars? surely it must find its natural 
home among the infinite, the infinitely remote 
both in space and in time!"* still caution linked 
with humility must be our watchword. For the 
utmost that we know is as nothing compared 
with the vast regions beyond which we do not 
know. 

Still the more yonder heavens are searched, 
the more it does appear that development takes 
place among those shining hosts, even as among 
the little existences on earth. 

Our moon, for instance, seems to be a very old 
and used-up world — old not so much in centuries 
or millenniums as in having reached a certain 
decrepid and worn-out phase of existence. One 
man is old and another is young at sixty. In 
actual decades of centuries the moon may reckon 
no more recurring birthdays than earth or sun ; 
but in the social standing of the skies she is, or 
seems to be, very elderly, very much paid out, 
almost a dead world. 

* Dr. Pritchard : " History of Research in Stellar Parallax." 



Further Thoughts. 325 

Once upon a time, doubtless, the moon was a 
shining mass of rotating gases, vague and nebu- 
lous in form, and that was her extreme youth — 
her infancy, so to speak. For her actual birth 
one would have to go farther back still. Then 
through ages, as gravitation drew the masses of 
gas nearer, she probably grew into a tiny sun or 
star, with a radiant photosphere and an atmo- 
sphere of heated gases in commotion. So tiny a 
sun would cool quickly ; and by-and-by the radi- 
ance would die out, as the little orb passed from 
vigorous youth to early middle life, reaching the 
present heated and molten but not luminous con- 
dition of Jupiter. After which would follow the 
advanced middle-age, such as our earth has now 
attained to ; though, if the moon had by that 
time lost her atmosphere, it could not well be an 
inhabited stage. Lastly she has gained her pres- 
ent half-dead phase of extreme old age. 

The sun is young still, in the very heyday of 
his existence. Though now a huge shapely ball, 
with a photosphere of radiant clouds and an envel- 
ope of heated gases, he was, probably, once upon 
a time, a vast nebula of revolving gases, like such 
nebulae as we see now in the skies. A mutual 
attraction drew the gas-particles slowly together, 



326 Sun, Moon, and Stars. 

his enormous hazy bulk gradually lessened and 
took a definite form. But still he continues and 
will steadily continue to lessen in size ; and this 
shrinkage is conjectured to cause the heat from 
which springs his glowing radiance. By-and-by, 
after countless ages, he may be expected to cool 
down further yet, first to a molten and then to a 
solid body, no longer giving out light or heat. 
Jupiter has passed from the gaseous and radiant 
to the heated but non-luminous condition. Earth, 
being smaller, has cooled and shrunk more rapid- 
ly than Jupiter, though by no means so rapidly as 
the still smaller moon. 

Thus in Sun, Jupiter, Earth, Moon we seem 
to see four distinct stages of star-life, the radiant 
vigor of youth, the calmer warmth of manhood, 
the composed usefulness of middle life, the used- 
up chilliness of extreme old age. 

This may have been — and, seemingly to us, it 
has been — the mode in which our God gradually, 
stage by stage, " made the stars " and " framed the 
worlds" which float in the universe. 

These few paces have been trodden. Step by 
step we have advanced, from the first early notion 
of our earth as the mighty centre of the universe 



F^lrther Thoughts. 327 

to a stage where earth and planets vanish from 
sight and the great central sun of our system him- 
self shines forth but as one glimmering point of 
light amid a million stars. 

Well may we say, in the words of the inspired 
writer, as we gaze on the wonders o£ God's glo- 
rious creation : 

" When I consider Thy heavens, the work of Thy 
fingers, the moon and the stars which Thou hast 
ordained, what is man that Thou art mindful of 
him ? and the son of man that Thou visitest him ?"* 

And yet there is another side to the matter. 
Infinite in power, God is also infinite in love. 
Mighty in the creation of his vast and blazing suns, 
he is no less mighty in the creation of a blade of 
grass. The rushing stars of a universe are in his 
hand, but not a sparrow on earth may fall to the 
ground without his knowledge. He guides each 
distant sun in its pathway through the sky, and 
also he looks from his throne of light to " ponder ° 
the ways of man. He tends His countless fur- 
naces of fire and flame ; yet " the very hairs of 
your head are all numbered/ ' 

Let us look into the matter as we will — let us 
weigh, measure, calculate — let us find our earth to 
* Psa. 8 : 3, 4. 



328 Sun, Moon, and Stars. 

be but as a grain of fine dust, lost amid myriads 
of worlds and suns. Still, at the close of all we 
stand face to face with the simple historical fact 
that the King of heaven, the Creator of the uni- 
verse, Himself lived as man for thirty-three years 
upon earth, died upon earth, rose from death upon 
earth, and went up again from earth to heaven. 
That sheds a distinguishing radiance upon our 
earth which, it may well be, no other world in all 
the universe can rival. 

"Thou art worthy, O Lord, to receive glory 
and honor and power : for Thou hast created all 
things, and for Thy pleasure they are and were 
created." Rev. 4 ill. 



TABLE OF SUBJECTS. 



PART I. 

Chap. I. What is the Earth? Olden beliefs. The Universe. 
Space. What are Stars ? Movements of Earth. Seeming 
Movements of Stars. The Evening Star. Planets 17—27 

Chap. II. The size of the Sun. The distance of the Sun from 
Earth. Size of Sun and Earth compared. Spots upon the Sun. 
Photosphere. Prominences. Storms on the Sun. Surface of 
the Sun 28 — 40 

Chap. III. The law of Attraction or Gravitation. A law of Motion. 
How both laws work together. What if the Earth went faster ? 
Two Motions of the Earth. Illustration with orange and knit- 
ting-needle. Day and Night. The Seasons. Speed of the 
Earth's surface at the Equator 41 — 54 

Chap. IV. Superior and Inferior Planets. Pathways of the Planets. 
Two Groups of Planets. Names of chief Planets. Mercury: 
his size, distance from sun, speed, and length of year. Venus: 
her size, distance from sun, speed, length of year, appearance 
as seen from earth, and phases. Mars: his size, distance from 
sun, length of day and year, speed and appearance. Moons of 
Mars. The Planetoids : their number, size, length of years, zone, 
and orbits 55 — 64 



33° Table of Subjects. 

Chap. V. Jupiter: his size, distance from sun, speed, cloudy cover- 
ing, length of day and year. Four Moons of Jupiter. Saturn: 
his distance from sun, size, length of day and year, motions, and 
cloudy covering. Moons and Rings of Saturn. Uranus: his 
distance from sun, size, speed, and length of year. Moons of 
Uranus. Neptune: his distance from sun, size, speed, length of 
year. Moon. Appearance* of sun seen from Neptune. What is 
meant by " a million miles." Size and distance. Supposed 
Models of Solar System 65 — 75 

Chap. VI. Journey to the Moon. Distance of the Moon from 
Earth. Size of the Moon. Two ways of thinking about the 
Moon. Motions of the Moon. Only one side seen from Earth. 
Moonland. Supposed Scenery. Supposed view of the heavens. 
Moon-mountains and plains. Craters. Shadows. Sunset and 
night in the Moon. Intense cold 76 — 87 

Chap. VII. Comets. Old dread of a collision. Nucleus, coma, and 
tail. Lightness of a Comet. Number of Comets known. Num- 
bers of Comets supposed to exist. Comet-visitors. Pathways 
of Comets. Singular nature of Comets. Changes seen to 
take place in Comets. Halley's Comet. Encke's Comet. New- 
ton's Comet 88 — 95 

Chap. VIII. Shooting Stars. A cannonade. Numbers of meteors 
seen nightly. Numbers supposed to fall daily to earth. What 
becomes of the Shooting - stars. Meteorite - dust. Aerolites. 
Meteors or fire-balls. Numbers of Meteor - systems met by 
earth. Numbers supposed to exist. August and November 
Rings. Grand displays every thirty - three years. Saturn's 
Rings. Zodiacal Light 96 — 104 

Chap. IX. Away from the Solar System. The Stars. How many 
stars are there ? Star-magnitudes. Distances of Stars. Meas- 



Table of Subjects, 331 

urement of distance. Distance of Alpha Centauri. Speed of 
Light. Light-journeyings from sun and stars 105 — 117 

Chap. X. Apparent movements of stars. Real movements of stars. 
Capella, Sinus, etc. Runaway stars. Arcturus: rate of speed. 
Journey of the sun. Where is he going? 118 — 131 



PART II. 

Chap. I. What the System contains. Is there Life on the Planets? 
Sun-rays and their work. Three Movements of the Earth. 
Journey of Sun through Space. Earth's orbit. Planets' orbits. 
How to draw a circle and an ellipse. Comets' orbits. Family 
influences. " Great " and " little." 135 — 148 

Chap. II. Sun-spots. Umbra, Penumbra, and Nucleus. Size of 
Spots. Possible explanation of Spots. Real and seeming 
changes in Spots. Sun-cyclones. Solar-outbursts and Magnets 
of Earth. "Willow-leaves." Eclipse of the Sun. Partial, Total, 
and Annular Eclipses. Eclipse of i860 149 — 161 

Chap. III. Storms seen at edge of Sun. Great solar outburst. 
Speed of hydrogen-cloud fragments. Red prominences, their 
shape and height. Corona described. Bulk and weight of 
Sun. Weight on surface of Sun. How far Attraction of Sun 
reaches 162 — 171 

Chap. IV. Is there Life on the Moon ? Size of Moon. Absence of 
Atmosphere. Reflected sunlight and earth-shine. Phases of 
Moon described. Illustration of Phases. Eclipse of the Moon. 
Total and Partial Eclipses 172 — 181 

Chap. V. Two ways of thinking about the Moon. Orbit of moon. 
Moon's motions governed by the Sun. Perturbations caused by 



332 Table of Subjects. 

Earth. Attraction of Moon and Ocean-tides. Unknown side of 
moon. No water in moon. Craters. Sunset - lights. Falling 
meteorites. Names of some chief Craters and Mountain- 
ranges 182 — 193 

Chap. VI. Mercury: his speed, length of day, slope of axis, orbit, 
varying distance from sun. Sun as seen from Mercury. Dense 
Atmosphere. Life on Mercury or no? Weight at surface of 
Mercury. Venus: her orbit. Transits of Mercury and Venus. 
Distance of Venus from Earth. Appearance and Phases of 
Venus. Appearance of Earth, seen from Venus. Length of day, 
climate, slanting axis of Venus. Life on Venus? Mars: his 
phases, moons, size, density, atmosphere, weather, geography, 
and distance from Earth. Water and Snow. Map of Mars. 
194 — 208 

Chap. VII. Jupiter: his size, weight, shape, slope of axis, turning 
on axis, seasons. Sun as seen from Jupiter. Jupiter seen 
through a telescope. Dark and bright Belts of Jupiter. Poles 
of Planets. Northern and southern heavens. West to east mo- 
tions of planets. Atmosphere of Jupiter. Possible explanation 
of Belts. Bright white spots. Motions of Jupiter's Bands. 
Winds and Hurricanes. Supposed present state of Jupiter. 
Life on Jupiter ? Jupiter's moons : their size, distance from 
Jupiter, eclipses, names 209 — 218 

Chap. VIII. Saturn : his size, weight, cloudy atmosphere, sup- 
posed present condition. Moons of Saturn. Square-shouldered 
appearance of Saturn. The Rings: their number, color, breadth. 
Shining of Rings by reflected light. Winter on Saturn. Ap- 
pearance of Saturn 219 — 226 

Chap. IX. Distance of Uranus from Saturn and from Neptune. 
Discovery of Uranus. Orbits of planets. Discovery of Neptune. 



Table of Subjects. 333 



Uranus and Neptune : their size, density, length of year, moons. 
Sun as seen from Uranus and Neptune 227 — 235 

Chap. X. Connection between Comets and Meteors. Meteor 
Rings. November System : supposed weight of Meteors. 
Grand display of 1866. Orbit of November System. Chief 
cluster : its supposed length, depth, and thickness. How 
many Meteor- Rings in the Solar System? 236 — 243 

Chap. XI. Comet of 181 1. Halley's Comet. Comet of 1843. 
Donati's Comet. Texture of a comet's tail. Weight of Comets. 
Changes seen in Comets. Motions of Comets. What are 
Comets and Meteorites made of? Meteorite dust. Supposi- 
tions. Comet-visitors, and where they come from 244 — 253 



PART III. 

Chap. I. Space beyond Solar System. Our Sun a Star. Speed of 
Light. Immense Distance of Stars. Distance of Alpha Cen- 
tauri. Sizes of Stars. Four chief orders of Stars. What Stars 
really are. Movements of Stars , 257 — 265 

Chap. II. 61 Cygni : double star, his speed, distance, weight. 
Alpha Centauri : double star, his position in heavens, speed, 
distance, weight. Sirius : his color, distance, size, motions, 
satellite. What Sirius is made of 266 — 2jj 

Chap. III. Variable Stars. Mira, Algol, Betelgeuse, Delta Cephei, 
Sun. Temporary Star of 1572. Two kinds of Double Stars. 
Quadruple Star near Vega. Stars of many colors. Examples 
of white, yellow, and red stars. Group of colored stars in 
southern heavens 278 — 286 



334 Table of Subjects. 



Chap. IV. The Milky Way. Globular Clusters. Colored Clusters. 
What are the Clusters ? Worlds without night. Nebulae. 
What are the Nebulae ? Nebulae in Orion. Different kinds of 
Nebulae. Magellanic Clouds 287 — 295 

Chap. V. Appearance of the Milky Way. What the Milky Way 
consists of. Sounding the Universe. The Cloven-Disc Theory. 
Ideas past and present. Arrangement of Stars in the sky. 
Motions of Stars. Motion of the Solar System. Supposed 
Model of the Universe 296 — 306 

Chap. VI. Spectrum Analysis. Metals: solid, liquid, and vapor 
forms. Metals in Sun and Stars. Use of a Prism. A broken- 
up ray of sunlight. Bands and Lines. Star-motions-- 307 — 316 

Chap. VII. Nova Aurigae. Atmospheres of heavenly bodies. 
Runaway Comets and Stars. Comparative ages of Sun, Jupiter, 
Earth, and Moon. Conclusion 317 — 328 



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